Граф коммитов

3519 Коммитов

Автор SHA1 Сообщение Дата
Oscar Salvador faf1c0008a x86/vmemmap: optimize for consecutive sections in partial populated PMDs
We can optimize in the case we are adding consecutive sections, so no
memset(PAGE_UNUSED) is needed.

In that case, let us keep track where the unused range of the previous
memory range begins, so we can compare it with start of the range to be
added.  If they are equal, we know sections are added consecutively.

For that purpose, let us introduce 'unused_pmd_start', which always holds
the beginning of the unused memory range.

In the case a section does not contiguously follow the previous one, we
know we can memset [unused_pmd_start, PMD_BOUNDARY) with PAGE_UNUSE.

This patch is based on a similar patch by David Hildenbrand:

https://lore.kernel.org/linux-mm/20200722094558.9828-10-david@redhat.com/

Link: https://lkml.kernel.org/r/20210309214050.4674-5-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:38 -07:00
Oscar Salvador 8d400913c2 x86/vmemmap: handle unpopulated sub-pmd ranges
When sizeof(struct page) is not a power of 2, sections do not span a PMD
anymore and so when populating them some parts of the PMD will remain
unused.

Because of this, PMDs will be left behind when depopulating sections since
remove_pmd_table() thinks that those unused parts are still in use.

Fix this by marking the unused parts with PAGE_UNUSED, so memchr_inv()
will do the right thing and will let us free the PMD when the last user of
it is gone.

This patch is based on a similar patch by David Hildenbrand:

https://lore.kernel.org/linux-mm/20200722094558.9828-9-david@redhat.com/

[osalvador@suse.de: go back to the ifdef version]
  Link: https://lkml.kernel.org/r/YGy++mSft7K4u+88@localhost.localdomain

Link: https://lkml.kernel.org/r/20210309214050.4674-4-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:38 -07:00
Oscar Salvador 69ccfe74e1 x86/vmemmap: drop handling of 1GB vmemmap ranges
There is no code to allocate 1GB pages when mapping the vmemmap range as
this might waste some memory and requires more complexity which is not
really worth.

Drop the dead code both for the aligned and unaligned cases and leave only
the direct map handling.

Link: https://lkml.kernel.org/r/20210309214050.4674-3-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:38 -07:00
Oscar Salvador 8e2df191ae x86/vmemmap: drop handling of 4K unaligned vmemmap range
Patch series "Cleanup and fixups for vmemmap handling", v6.

This series contains cleanups to remove dead code that handles unaligned
cases for 4K and 1GB pages (patch#1 and patch#2) when removing the vemmmap
range, and a fix (patch#3) to handle the case when two vmemmap ranges
intersect the same PMD.

This patch (of 4):

remove_pte_table() is prepared to handle the case where either the start
or the end of the range is not PAGE aligned.  This cannot actually happen:

__populate_section_memmap enforces the range to be PMD aligned, so as long
as the size of the struct page remains multiple of 8, the vmemmap range
will be aligned to PAGE_SIZE.

Drop the dead code and place a VM_BUG_ON in vmemmap_{populate,free} to
catch nasty cases.  Note that the VM_BUG_ON is placed in there because
vmemmap_{populate,free= } is the gate of all removing and freeing page
tables logic.

Link: https://lkml.kernel.org/r/20210309214050.4674-1-osalvador@suse.de
Link: https://lkml.kernel.org/r/20210309214050.4674-2-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:38 -07:00
Linus Torvalds 635de956a7 The x86 MM changes in this cycle were:
- Implement concurrent TLB flushes, which overlaps the local TLB flush with the
    remote TLB flush. In testing this improved sysbench performance measurably by
    a couple of percentage points, especially if TLB-heavy security mitigations
    are active.
 
  - Further micro-optimizations to improve the performance of TLB flushes.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmCKbNcRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1hjYBAAsyNUa/gOu0g6/Cx8R86w9HtHHmm5vso/
 6nJjWj2fd2qJ9JShlddxvXEMeXtPTYabVWQkiiriFMuofk6JeKnlHm1Jzl6keABX
 OQFwjIFeNASPRcdXvuuYPOVWAJJdr2oL9QUr6OOK1ccQJTz/Cd0zA+VQ5YqcsCon
 yaWbkxELwKXpgql+qt66eAZ6Q2Y1TKXyrTW7ZgxQi0yeeWqMaEOub0/oyS7Ax1Rg
 qEJMwm1prb76NPzeqR/G3e4KTrDZfQ/B/KnSsz36GTJpl4eye6XqWDUgm1nAGNIc
 5dbc4Vx7JtZsUOuC0AmzWb3hsDyzVcN/lQvijdZ2RsYR3gvuYGaBhKqExqV0XH6P
 oqaWOKWCz+LqWbsgJmxCpqkt1LZl5+VUOcfJ97WkIS7DyIPtSHTzQXbBMZqKLeat
 mn5UcKYB2Gi7wsUPv6VC2ChKbDqN0VT8G86XbYylGo4BE46KoZKPUNY/QWKLUPd6
 0UKcVeNM2HFyf1C73p/tO/z7hzu3qLuMMnsphP6/c2pKLpdgawEXgbnVKNId1B/c
 NrzyhTvVaMt+Um28bBRhHONIlzPJwWcnZbdY7NqMnu+LBKQ68cL/h4FOIV/RDLNb
 GJLgfAr8fIw/zIpqYuFHiiMNo9wWqVtZko1MvXhGceXUL69QuzTra2XR/6aDxkPf
 6gQVesetTvo=
 =3Cyp
 -----END PGP SIGNATURE-----

Merge tag 'x86-mm-2021-04-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 tlb updates from Ingo Molnar:
 "The x86 MM changes in this cycle were:

   - Implement concurrent TLB flushes, which overlaps the local TLB
     flush with the remote TLB flush.

     In testing this improved sysbench performance measurably by a
     couple of percentage points, especially if TLB-heavy security
     mitigations are active.

   - Further micro-optimizations to improve the performance of TLB
     flushes"

* tag 'x86-mm-2021-04-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Micro-optimize smp_call_function_many_cond()
  smp: Inline on_each_cpu_cond() and on_each_cpu()
  x86/mm/tlb: Remove unnecessary uses of the inline keyword
  cpumask: Mark functions as pure
  x86/mm/tlb: Do not make is_lazy dirty for no reason
  x86/mm/tlb: Privatize cpu_tlbstate
  x86/mm/tlb: Flush remote and local TLBs concurrently
  x86/mm/tlb: Open-code on_each_cpu_cond_mask() for tlb_is_not_lazy()
  x86/mm/tlb: Unify flush_tlb_func_local() and flush_tlb_func_remote()
  smp: Run functions concurrently in smp_call_function_many_cond()
2021-04-29 11:41:43 -07:00
Linus Torvalds ea5bc7b977 Trivial cleanups and fixes all over the place.
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmCGmYIACgkQEsHwGGHe
 VUr45w/8CSXr7MXaFBj4To0hTWJXSZyF6YGqlZOSJXFcFh4cWTNwfVOoFaV47aDo
 +HsCNTkGENcKhLrDUWDRiG/Uo46jxtOtl1vhq7U4pGemSYH871XWOKfb5k5XNMwn
 /uhaHMI4aEfd6bUFnF518NeyRIsD0BdqFj4tB7RbAiyFwdETDX9Tkj/uBKnQ4zon
 4tEDoXgThuK5YKK9zVQg5pa7aFp2zg1CAdX/WzBkS8BHVBPXSV0CF97AJYQOM/V+
 lUHv+BN3wp97GYHPQMPsbkNr8IuFoe2mIvikwjxg8iOFpzEU1G1u09XV9R+PXByX
 LclFTRqK/2uU5hJlcsBiKfUuidyErYMRYImbMAOREt2w0ogWVu2zQ7HkjVve25h1
 sQPwPudbAt6STbqRxvpmB3yoV4TCYwnF91FcWgEy+rcEK2BDsHCnScA45TsK5I1C
 kGR1K17pHXprgMZFPveH+LgxewB6smDv+HllxQdSG67LhMJXcs2Epz0TsN8VsXw8
 dlD3lGReK+5qy9FTgO7mY0xhiXGz1IbEdAPU4eRBgih13puu03+jqgMaMabvBWKD
 wax+BWJUrPtetwD5fBPhlS/XdJDnd8Mkv2xsf//+wT0s4p+g++l1APYxeB8QEehm
 Pd7Mvxm4GvQkfE13QEVIPYQRIXCMH/e9qixtY5SHUZDBVkUyFM0=
 =bO1i
 -----END PGP SIGNATURE-----

Merge tag 'x86_cleanups_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull misc x86 cleanups from Borislav Petkov:
 "Trivial cleanups and fixes all over the place"

* tag 'x86_cleanups_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Remove me from IDE/ATAPI section
  x86/pat: Do not compile stubbed functions when X86_PAT is off
  x86/asm: Ensure asm/proto.h can be included stand-alone
  x86/platform/intel/quark: Fix incorrect kernel-doc comment syntax in files
  x86/msr: Make locally used functions static
  x86/cacheinfo: Remove unneeded dead-store initialization
  x86/process/64: Move cpu_current_top_of_stack out of TSS
  tools/turbostat: Unmark non-kernel-doc comment
  x86/syscalls: Fix -Wmissing-prototypes warnings from COND_SYSCALL()
  x86/fpu/math-emu: Fix function cast warning
  x86/msr: Fix wr/rdmsr_safe_regs_on_cpu() prototypes
  x86: Fix various typos in comments, take #2
  x86: Remove unusual Unicode characters from comments
  x86/kaslr: Return boolean values from a function returning bool
  x86: Fix various typos in comments
  x86/setup: Remove unused RESERVE_BRK_ARRAY()
  stacktrace: Move documentation for arch_stack_walk_reliable() to header
  x86: Remove duplicate TSC DEADLINE MSR definitions
2021-04-26 09:25:47 -07:00
Linus Torvalds 26a4ef7e48 Add support for SEV-ES guests booting through the 32-bit boot path, along with
cleanups, fixes and improvements.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmCGkbQACgkQEsHwGGHe
 VUrJ4w/+M9TbCppcILNvtaHn0mgpcDVmKvRSDdLl/MWcW1kuzczcdFYAK+OFFD0E
 TYKSEmkJUz3Tm0YBkO9PSPTBk+hnduPunXRk2Mzse1Uv3LxPuWEN3q6ZAfP1rOZ1
 3nlEnzHCWZdf4d7uz49qCXj96bfv98+zU2DaCoVoNUImp8jzo6hMtTPI4N31Tply
 Rb0b0acIkdmy0eaADilMciimZevs9EF3KgiwSd0AUAJE1aRtRpPKtv2F1OraJPkH
 T7AunJvoO8Sb2vpHfaW8iZrx2HKE8KZ4QOfM+dAXurjadlPVBLN34MC8FIw4tIS+
 m2dc/CMaVy1QpyHKOTZqY9ZsCndunrMJXsolhCyBjA6fAZ1aFZswxRWUeGrOkCJ2
 ZGJetB0tADi0gIRZerwyPXOKLiJBo8BSmIr8FzHq8CYYoxKH9D1dqEZVj9kBcGLJ
 SYbgUIKNuw54RzE00S8i2s625RG5A7qn6GrRMvnkVyJnKoD01na0trND2AbufBJz
 oDhBXfvP5SwswEt4YYZ1rn3JO1nRZzn4WGfiUQ4ElOEFYuUEZOJtcw1LHwDJ0LcQ
 bfOs0mmDFajFH1DyILyHfji4rdqHGWIpGIHfmYs98Njtfa8dtximU/csr69by/xV
 dcycXbPaw5psDe4Acw2vb7DM7h7T9fHNG+VgRJb25gXeywGutac=
 =AUGR
 -----END PGP SIGNATURE-----

Merge tag 'x86_seves_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 AMD secure virtualization (SEV-ES) updates from Borislav Petkov:
 "Add support for SEV-ES guests booting through the 32-bit boot path,
  along with cleanups, fixes and improvements"

* tag 'x86_seves_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sev-es: Optimize __sev_es_ist_enter() for better readability
  x86/sev-es: Replace open-coded hlt-loops with sev_es_terminate()
  x86/boot/compressed/64: Check SEV encryption in the 32-bit boot-path
  x86/boot/compressed/64: Add CPUID sanity check to 32-bit boot-path
  x86/boot/compressed/64: Add 32-bit boot #VC handler
  x86/boot/compressed/64: Setup IDT in startup_32 boot path
  x86/boot/compressed/64: Reload CS in startup_32
  x86/sev: Do not require Hypervisor CPUID bit for SEV guests
  x86/boot/compressed/64: Cleanup exception handling before booting kernel
  x86/virtio: Have SEV guests enforce restricted virtio memory access
  x86/sev-es: Remove subtraction of res variable
2021-04-26 09:11:10 -07:00
Sean Christopherson 4daf2a1c45 x86/sev: Drop redundant and potentially misleading 'sev_enabled'
Drop the sev_enabled flag and switch its one user over to sev_active().
sev_enabled was made redundant with the introduction of sev_status in
commit b57de6cd16 ("x86/sev-es: Add SEV-ES Feature Detection").
sev_enabled and sev_active() are guaranteed to be equivalent, as each is
true iff 'sev_status & MSR_AMD64_SEV_ENABLED' is true, and are only ever
written in tandem (ignoring compressed boot's version of sev_status).

Removing sev_enabled avoids confusion over whether it refers to the guest
or the host, and will also allow KVM to usurp "sev_enabled" for its own
purposes.

No functional change intended.

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210422021125.3417167-7-seanjc@google.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-26 05:27:14 -04:00
Jan Kiszka 16854b567d x86/pat: Do not compile stubbed functions when X86_PAT is off
Those are already provided by linux/io.h as stubs.

The conflict remains invisible until someone would pull linux/io.h into
memtype.c. This fixes a build error when this file is used outside of
the kernel tree.

  [ bp: Massage commit message. ]

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/a9351615-7a0d-9d47-af65-d9e2fffe8192@siemens.com
2021-04-14 08:21:41 +02:00
Lai Jiangshan 1591584e2e x86/process/64: Move cpu_current_top_of_stack out of TSS
cpu_current_top_of_stack is currently stored in TSS.sp1. TSS is exposed
through the cpu_entry_area which is visible with user CR3 when PTI is
enabled and active.

This makes it a coveted fruit for attackers.  An attacker can fetch the
kernel stack top from it and continue next steps of actions based on the
kernel stack.

But it is actualy not necessary to be stored in the TSS.  It is only
accessed after the entry code switched to kernel CR3 and kernel GS_BASE
which means it can be in any regular percpu variable.

The reason why it is in TSS is historical (pre PTI) because TSS is also
used as scratch space in SYSCALL_64 and therefore cache hot.

A syscall also needs the per CPU variable current_task and eventually
__preempt_count, so placing cpu_current_top_of_stack next to them makes it
likely that they end up in the same cache line which should avoid
performance regressions. This is not enforced as the compiler is free to
place these variables, so these entry relevant variables should move into
a data structure to make this enforceable.

The seccomp_benchmark doesn't show any performance loss in the "getpid
native" test result.  Actually, the result changes from 93ns before to 92ns
with this change when KPTI is disabled. The test is very stable and
although the test doesn't show a higher degree of precision it gives enough
confidence that moving cpu_current_top_of_stack does not cause a
regression.

[ tglx: Removed unneeded export. Massaged changelog ]

Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210125173444.22696-2-jiangshanlai@gmail.com
2021-03-28 22:40:10 +02:00
Isaku Yamahata 8249d17d31 x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc()
The pfn variable contains the page frame number as returned by the
pXX_pfn() functions, shifted to the right by PAGE_SHIFT to remove the
page bits. After page protection computations are done to it, it gets
shifted back to the physical address using page_level_shift().

That is wrong, of course, because that function determines the shift
length based on the level of the page in the page table but in all the
cases, it was shifted by PAGE_SHIFT before.

Therefore, shift it back using PAGE_SHIFT to get the correct physical
address.

 [ bp: Rewrite commit message. ]

Fixes: dfaaec9033 ("x86: Add support for changing memory encryption attribute in early boot")
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/81abbae1657053eccc535c16151f63cd049dcb97.1616098294.git.isaku.yamahata@intel.com
2021-03-23 11:59:45 +01:00
Ingo Molnar 163b099146 x86: Fix various typos in comments, take #2
Fix another ~42 single-word typos in arch/x86/ code comments,
missed a few in the first pass, in particular in .S files.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org
2021-03-21 23:50:28 +01:00
Joerg Roedel eab696d8e8 x86/sev: Do not require Hypervisor CPUID bit for SEV guests
A malicious hypervisor could disable the CPUID intercept for an SEV or
SEV-ES guest and trick it into the no-SEV boot path, where it could
potentially reveal secrets. This is not an issue for SEV-SNP guests,
as the CPUID intercept can't be disabled for those.

Remove the Hypervisor CPUID bit check from the SEV detection code to
protect against this kind of attack and add a Hypervisor bit equals zero
check to the SME detection path to prevent non-encrypted guests from
trying to enable SME.

This handles the following cases:

	1) SEV(-ES) guest where CPUID intercept is disabled. The guest
	   will still see leaf 0x8000001f and the SEV bit. It can
	   retrieve the C-bit and boot normally.

	2) Non-encrypted guests with intercepted CPUID will check
	   the SEV_STATUS MSR and find it 0 and will try to enable SME.
	   This will fail when the guest finds MSR_K8_SYSCFG to be zero,
	   as it is emulated by KVM. But we can't rely on that, as there
	   might be other hypervisors which return this MSR with bit
	   23 set. The Hypervisor bit check will prevent that the guest
	   tries to enable SME in this case.

	3) Non-encrypted guests on SEV capable hosts with CPUID intercept
	   disabled (by a malicious hypervisor) will try to boot into
	   the SME path. This will fail, but it is also not considered
	   a problem because non-encrypted guests have no protection
	   against the hypervisor anyway.

 [ bp: s/non-SEV/non-encrypted/g ]

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lkml.kernel.org/r/20210312123824.306-3-joro@8bytes.org
2021-03-18 16:44:40 +01:00
Ingo Molnar d9f6e12fb0 x86: Fix various typos in comments
Fix ~144 single-word typos in arch/x86/ code comments.

Doing this in a single commit should reduce the churn.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org
2021-03-18 15:31:53 +01:00
Tom Lendacky 229164175f x86/virtio: Have SEV guests enforce restricted virtio memory access
An SEV guest requires that virtio devices use the DMA API to allow the
hypervisor to successfully access guest memory as needed.

The VIRTIO_F_VERSION_1 and VIRTIO_F_ACCESS_PLATFORM features tell virtio
to use the DMA API. Add arch_has_restricted_virtio_memory_access() for
x86, to fail the device probe if these features have not been set for the
device when running as an SEV guest.

 [ bp: Fix -Wmissing-prototypes warning
   Reported-by: kernel test robot <lkp@intel.com> ]

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/b46e0211f77ca1831f11132f969d470a6ffc9267.1614897610.git.thomas.lendacky@amd.com
2021-03-08 20:41:33 +01:00
Nadav Amit 1608e4cf31 x86/mm/tlb: Remove unnecessary uses of the inline keyword
The compiler is smart enough without these hints.

Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-9-namit@vmware.com
2021-03-06 12:59:10 +01:00
Nadav Amit 09c5272e48 x86/mm/tlb: Do not make is_lazy dirty for no reason
Blindly writing to is_lazy for no reason, when the written value is
identical to the old value, makes the cacheline dirty for no reason.
Avoid making such writes to prevent cache coherency traffic for no
reason.

Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-7-namit@vmware.com
2021-03-06 12:59:10 +01:00
Nadav Amit 2f4305b19f x86/mm/tlb: Privatize cpu_tlbstate
cpu_tlbstate is mostly private and only the variable is_lazy is shared.
This causes some false-sharing when TLB flushes are performed.

Break cpu_tlbstate intro cpu_tlbstate and cpu_tlbstate_shared, and mark
each one accordingly.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-6-namit@vmware.com
2021-03-06 12:59:10 +01:00
Nadav Amit 4ce94eabac x86/mm/tlb: Flush remote and local TLBs concurrently
To improve TLB shootdown performance, flush the remote and local TLBs
concurrently. Introduce flush_tlb_multi() that does so. Introduce
paravirtual versions of flush_tlb_multi() for KVM, Xen and hyper-v (Xen
and hyper-v are only compile-tested).

While the updated smp infrastructure is capable of running a function on
a single local core, it is not optimized for this case. The multiple
function calls and the indirect branch introduce some overhead, and
might make local TLB flushes slower than they were before the recent
changes.

Before calling the SMP infrastructure, check if only a local TLB flush
is needed to restore the lost performance in this common case. This
requires to check mm_cpumask() one more time, but unless this mask is
updated very frequently, this should impact performance negatively.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> # Hyper-v parts
Reviewed-by: Juergen Gross <jgross@suse.com> # Xen and paravirt parts
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-5-namit@vmware.com
2021-03-06 12:59:10 +01:00
Nadav Amit 6035152d8e x86/mm/tlb: Open-code on_each_cpu_cond_mask() for tlb_is_not_lazy()
Open-code on_each_cpu_cond_mask() in native_flush_tlb_others() to
optimize the code. Open-coding eliminates the need for the indirect branch
that is used to call is_lazy(), and in CPUs that are vulnerable to
Spectre v2, it eliminates the retpoline. In addition, it allows to use a
preallocated cpumask to compute the CPUs that should be.

This would later allow us not to adapt on_each_cpu_cond_mask() to
support local and remote functions.

Note that calling tlb_is_not_lazy() for every CPU that needs to be
flushed, as done in native_flush_tlb_multi() might look ugly, but it is
equivalent to what is currently done in on_each_cpu_cond_mask().
Actually, native_flush_tlb_multi() does it more efficiently since it
avoids using an indirect branch for the matter.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-4-namit@vmware.com
2021-03-06 12:59:09 +01:00
Nadav Amit 4c1ba3923e x86/mm/tlb: Unify flush_tlb_func_local() and flush_tlb_func_remote()
The unification of these two functions allows to use them in the updated
SMP infrastrucutre.

To do so, remove the reason argument from flush_tlb_func_local(), add
a member to struct tlb_flush_info that says which CPU initiated the
flush and act accordingly. Optimize the size of flush_tlb_info while we
are at it.

Unfortunately, this prevents us from using a constant tlb_flush_info for
arch_tlbbatch_flush(), but in a later stage we may be able to inline
tlb_flush_info into the IPI data, so it should not have an impact
eventually.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-3-namit@vmware.com
2021-03-06 12:59:09 +01:00
NeilBrown 3d2fc4c082 x86: fix seq_file iteration for pat/memtype.c
The memtype seq_file iterator allocates a buffer in the ->start and ->next
functions and frees it in the ->show function.  The preferred handling for
such resources is to free them in the subsequent ->next or ->stop function
call.

Since Commit 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration
code and interface") there is no guarantee that ->show will be called
after ->next, so this function can now leak memory.

So move the freeing of the buffer to ->next and ->stop.

Link: https://lkml.kernel.org/r/161248539022.21478.13874455485854739066.stgit@noble1
Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code and interface")
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Xin Long <lucien.xin@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:05 -08:00
Marco Elver bc8fbc5f30 kfence: add test suite
Add KFENCE test suite, testing various error detection scenarios. Makes
use of KUnit for test organization. Since KFENCE's interface to obtain
error reports is via the console, the test verifies that KFENCE outputs
expected reports to the console.

[elver@google.com: fix typo in test]
  Link: https://lkml.kernel.org/r/X9lHQExmHGvETxY4@elver.google.com
[elver@google.com: show access type in report]
  Link: https://lkml.kernel.org/r/20210111091544.3287013-2-elver@google.com

Link: https://lkml.kernel.org/r/20201103175841.3495947-9-elver@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Co-developed-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:02 -08:00
Marco Elver d438fabce7 kfence: use pt_regs to generate stack trace on faults
Instead of removing the fault handling portion of the stack trace based on
the fault handler's name, just use struct pt_regs directly.

Change kfence_handle_page_fault() to take a struct pt_regs, and plumb it
through to kfence_report_error() for out-of-bounds, use-after-free, or
invalid access errors, where pt_regs is used to generate the stack trace.

If the kernel is a DEBUG_KERNEL, also show registers for more information.

Link: https://lkml.kernel.org/r/20201105092133.2075331-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:02 -08:00
Alexander Potapenko 1dc0da6e9e x86, kfence: enable KFENCE for x86
Add architecture specific implementation details for KFENCE and enable
KFENCE for the x86 architecture. In particular, this implements the
required interface in <asm/kfence.h> for setting up the pool and
providing helper functions for protecting and unprotecting pages.

For x86, we need to ensure that the pool uses 4K pages, which is done
using the set_memory_4k() helper function.

[elver@google.com: add missing copyright and description header]
  Link: https://lkml.kernel.org/r/20210118092159.145934-2-elver@google.com

Link: https://lkml.kernel.org/r/20201103175841.3495947-3-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Co-developed-by: Marco Elver <elver@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:02 -08:00
Linus Torvalds ae821d2107 - PTRACE_GETREGS/PTRACE_PUTREGS regset selection cleanup
- Another initial cleanup - more to follow - to the fault handling code.
 
 - Other minor cleanups and corrections.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmAqU0oACgkQEsHwGGHe
 VUruWw//VA+/K7Ykd8tjZdmJPWdfsdqBtOrolh4hiajM6iYckTip/FdwHpeEQwM9
 ff0iNMrxICG3gbQxCX6WNzPeJatYsnjtF67whfat2SEzNHSDtZDb1Bm20s2/1fbY
 OurRBTEBzuYMolpEJ2XABpu7LQ+6TV3LJ6yUBungILMOjP7KvrCK0SUrWj253VDU
 XljK5XBZnmYlEjPU6dlhn64Wsl/GD7AWCAeZGq47EgjH2cR6gxNmu9kYAArGbdiJ
 WjF8MWE7qVwCPUTiCBv+P1CjsQawvlcUY54wtG65dBYAZvpjmN82T2ypguzAt8KT
 12A38vFlBuEUAWC0rUymNouh8Q20AElpdw/odLElHkpNxbHhf/7RyZ1E00LjsFtn
 MF9Gp9aSIQbfYWK+Hin9oRvqXckV08u3KtzUNeyMbdCmpyqHh6prj8JEZaxKZZUp
 zCaX8Qasn+Q9zL0DO51WI9EPOwpvSpifUYHmd5RHGbQDW9DjYK4mkBCHhjVfYXd/
 NcxRO5rrMLmMG+XuNPg9vuHMi2HJnClJ6odD6b80xGvBodTZxZnqnYO9tUImbYnW
 pdmt73YDvakei8XY7cAdNWcsTi0kQYZGfInna6z43Ri2l+I1TZaoKGDqn7TbzNbb
 9RB0lrD0tfW0PvvDbVwco0Q+8/ykIbvPkHPvjQGWioxHi6yI49s=
 =uVEk
 -----END PGP SIGNATURE-----

Merge tag 'x86_mm_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm cleanups from Borislav Petkov:

 - PTRACE_GETREGS/PTRACE_PUTREGS regset selection cleanup

 - Another initial cleanup - more to follow - to the fault handling
   code.

 - Other minor cleanups and corrections.

* tag 'x86_mm_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/{fault,efi}: Fix and rename efi_recover_from_page_fault()
  x86/fault: Don't run fixups for SMAP violations
  x86/fault: Don't look for extable entries for SMEP violations
  x86/fault: Rename no_context() to kernelmode_fixup_or_oops()
  x86/fault: Bypass no_context() for implicit kernel faults from usermode
  x86/fault: Split the OOPS code out from no_context()
  x86/fault: Improve kernel-executing-user-memory handling
  x86/fault: Correct a few user vs kernel checks wrt WRUSS
  x86/fault: Document the locking in the fault_signal_pending() path
  x86/fault/32: Move is_f00f_bug() to do_kern_addr_fault()
  x86/fault: Fold mm_fault_error() into do_user_addr_fault()
  x86/fault: Skip the AMD erratum #91 workaround on unaffected CPUs
  x86/fault: Fix AMD erratum #91 errata fixup for user code
  x86/Kconfig: Remove HPET_EMULATE_RTC depends on RTC
  x86/asm: Fixup TASK_SIZE_MAX comment
  x86/ptrace: Clean up PTRACE_GETREGS/PTRACE_PUTREGS regset selection
  x86/vm86/32: Remove VM86_SCREEN_BITMAP support
  x86: Remove definition of DEBUG
  x86/entry: Remove now unused do_IRQ() declaration
  x86/mm: Remove duplicate definition of _PAGE_PAT_LARGE
  ...
2021-02-20 19:34:09 -08:00
Linus Torvalds b9cdab6820 Do not unroll string I/O for SEV-ES guests because they support it.
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmAqT+UACgkQEsHwGGHe
 VUr1hQ//d4lgbpkXAq17f/43kMZK5GJKMocdBZw+6QmUr4TYWS2PPTfXEr4FCjM1
 NqxR2wo97bjbg0oHZOd0JzjxzhC6fHXwiyyFGRv3sS7WNfVPlJRZ47dNa1qPxuZX
 QjFwjtWtR2YzKue5Xq7O87gf2YEWFgojWRd5cCyqNU2a0SAHSOhNij8vSswXaBZA
 tD2ApIlce1de4HJxXXFBN9xAows7EqKH4OTqRld66aUqDsUfLQCdPB0aKqnTpItA
 pzW6TRM392K97j2jvMjEJsHcRUVdsYvE8ICz36vk2vmpP1V3stPxOW8lfC4JV5dL
 NXmhuol+CzW/3FeyW5wTtmhJRj3I5MvPl3ddf30Ex9tXSx1RT/7VU7p/zDcv81WZ
 32bQFYnPeNI0SHXH+CW7p13GWDE+yTBCUy838Olmkx69K+2OBgt5B6W2BcOkiKPN
 RH1NAkwxhjP53eR7CIjirvKK77/p/48/Jg2TyLVWKHcdr7QPZdFG0+FpYbQ2nKoj
 q2Gy7l/uxTciu7/RTRHM3E/STVqEmrWSjIuy+dhTOJaHqjMXPyiWXWdYgH2QymUX
 pkTi72uaHy5HF0DyOo5pONkJrODUBasr1iJxUKuWkR++wLJihxN5+lbTxd9Vvcop
 KN5HNhLoyyQ8jYuc8OLwoHIDEskJgMqLDfNx9sLqCXfR380FfAc=
 =anHE
 -----END PGP SIGNATURE-----

Merge tag 'x86_seves_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SEV-ES fix from Borislav Petkov:
 "Do not unroll string I/O for SEV-ES guests because they support it"

* tag 'x86_seves_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sev-es: Do not unroll string I/O for SEV-ES guests
2021-02-20 19:16:02 -08:00
Ingo Molnar 40c1fa52cd Merge branch 'x86/cleanups' into x86/mm
Merge recent cleanups to the x86 MM code to resolve a conflict.

Conflicts:
	arch/x86/mm/fault.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-12 13:40:02 +01:00
Andy Lutomirski c46f52231e x86/{fault,efi}: Fix and rename efi_recover_from_page_fault()
efi_recover_from_page_fault() doesn't recover -- it does a special EFI
mini-oops.  Rename it to make it clear that it crashes.

While renaming it, I noticed a blatant bug: a page fault oops in a
different thread happening concurrently with an EFI runtime service call
would be misinterpreted as an EFI page fault.  Fix that.

This isn't quite exact. The situation could be improved by using a
special CS for calls into EFI.

 [ bp: Massage commit message and simplify in interrupt check. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/f43b1e80830dc78ed60ed8b0826f4f189254570c.1612924255.git.luto@kernel.org
2021-02-10 18:39:23 +01:00
Andy Lutomirski ca24728378 x86/fault: Don't run fixups for SMAP violations
A SMAP-violating kernel access is not a recoverable condition.  Imagine
kernel code that, outside of a uaccess region, dereferences a pointer to
the user range by accident.  If SMAP is on, this will reliably generate
as an intentional user access.  This makes it easy for bugs to be
overlooked if code is inadequately tested both with and without SMAP.

This was discovered because BPF can generate invalid accesses to user
memory, but those warnings only got printed if SMAP was off. Make it so
that this type of error will be discovered with SMAP on as well.

 [ bp: Massage commit message. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/66a02343624b1ff46f02a838c497fc05c1a871b3.1612924255.git.luto@kernel.org
2021-02-10 16:27:57 +01:00
Andy Lutomirski 66fcd98883 x86/fault: Don't look for extable entries for SMEP violations
If the kernel gets a SMEP violation or a fault that would have been a
SMEP violation if it had SMEP support, it shouldn't run fixups. Just
OOPS.

 [ bp: Massage commit message. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/46160d8babce2abf1d6daa052146002efa24ac56.1612924255.git.luto@kernel.org
2021-02-10 14:45:39 +01:00
Andy Lutomirski 6456a2a69e x86/fault: Rename no_context() to kernelmode_fixup_or_oops()
The name no_context() has never been very clear.  It's only called for
faults from kernel mode, so rename it and change the no-longer-useful
user_mode(regs) check to a WARN_ON_ONCE.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/c21940efe676024bb4bc721f7d70c29c420e127e.1612924255.git.luto@kernel.org
2021-02-10 14:41:19 +01:00
Andy Lutomirski 5042d40a26 x86/fault: Bypass no_context() for implicit kernel faults from usermode
Drop an indentation level and remove the last user_mode(regs) == true
caller of no_context() by directly OOPSing for implicit kernel faults
from usermode.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/6e3d1129494a8de1e59d28012286e3a292a2296e.1612924255.git.luto@kernel.org
2021-02-10 14:39:52 +01:00
Andy Lutomirski 2cc624b0a7 x86/fault: Split the OOPS code out from no_context()
Not all callers of no_context() want to run exception fixups.
Separate the OOPS code out from the fixup code in no_context().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/450f8d8eabafb83a5df349108c8e5ea83a2f939d.1612924255.git.luto@kernel.org
2021-02-10 14:33:36 +01:00
Andy Lutomirski 03c81ea333 x86/fault: Improve kernel-executing-user-memory handling
Right now, the case of the kernel trying to execute from user memory
is treated more or less just like the kernel getting a page fault on a
user access. In the failure path, it checks for erratum #93, tries to
otherwise fix up the error, and then oopses.

If it manages to jump to the user address space, with or without SMEP,
it should not try to resolve the page fault. This is an error, pure and
simple. Rearrange the code so that this case is caught early, check for
erratum #93, and bail out.

 [ bp: Massage commit message. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/ab8719c7afb8bd501c4eee0e36493150fbbe5f6a.1612924255.git.luto@kernel.org
2021-02-10 14:20:54 +01:00
Andy Lutomirski 56e62cd28a x86/fault: Correct a few user vs kernel checks wrt WRUSS
In general, page fault errors for WRUSS should be just like get_user(),
etc.  Fix three bugs in this area:

There is a comment that says that, if the kernel can't handle a page fault
on a user address due to OOM, the OOM-kill-and-retry logic would be
skipped.  The code checked kernel *privilege*, not kernel mode, so it
missed WRUSS.  This means that the kernel would malfunction if it got OOM
on a WRUSS fault -- this would be a kernel-mode, user-privilege fault, and
the OOM killer would be invoked and the handler would retry the faulting
instruction.

A failed user access from kernel while a fatal signal is pending should
fail even if the instruction in question was WRUSS.

do_sigbus() should not send SIGBUS for WRUSS -- it should handle it like
any other kernel mode failure.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/a7b7bcea730bd4069e6b7e629236bb2cf526c2fb.1612924255.git.luto@kernel.org
2021-02-10 14:13:32 +01:00
Andy Lutomirski ef2544fb3f x86/fault: Document the locking in the fault_signal_pending() path
If fault_signal_pending() returns true, then the core mm has unlocked the
mm for us.  Add a comment to help future readers of this code.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/c56de3d103f40e6304437b150aa7b215530d23f7.1612924255.git.luto@kernel.org
2021-02-10 14:12:07 +01:00
Andy Lutomirski f42a40fd53 x86/fault/32: Move is_f00f_bug() to do_kern_addr_fault()
bad_area() and its relatives are called from many places in fault.c, and
exactly one of them wants the F00F workaround.

__bad_area_nosemaphore() no longer contains any kernel fault code, which
prepares for further cleanups.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/e9668729a48ce6754022b0a4415631e8ebdd00e7.1612924255.git.luto@kernel.org
2021-02-10 14:11:07 +01:00
Andy Lutomirski ec352711ce x86/fault: Fold mm_fault_error() into do_user_addr_fault()
mm_fault_error() is logically just the end of do_user_addr_fault().
Combine the functions.  This makes the code easier to read.

Most of the churn here is from renaming hw_error_code to error_code in
do_user_addr_fault().

This makes no difference at all to the generated code (objdump -dr) as
compared to changing noinline to __always_inline in the definition of
mm_fault_error().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/dedc4d9c9b047e51ce38b991bd23971a28af4e7b.1612924255.git.luto@kernel.org
2021-02-10 14:10:07 +01:00
Andy Lutomirski d24df8ecf9 x86/fault: Skip the AMD erratum #91 workaround on unaffected CPUs
According to the Revision Guide for AMD Athlon™ 64 and AMD Opteron™
Processors, only early revisions of family 0xF are affected. This will
avoid unnecessarily fetching instruction bytes before sending SIGSEGV to
user programs.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/477173b7784bc28afb3e53d76ae5ef143917e8dd.1612924255.git.luto@kernel.org
2021-02-10 13:38:12 +01:00
Andy Lutomirski 35f1c89b0c x86/fault: Fix AMD erratum #91 errata fixup for user code
The recent rework of probe_kernel_address() and its conversion to
get_kernel_nofault() inadvertently broke is_prefetch(). Before this
change, probe_kernel_address() was used as a sloppy "read user or
kernel memory" helper, but it doesn't do that any more. The new
get_kernel_nofault() reads *kernel* memory only, which completely broke
is_prefetch() for user access.

Adjust the code to the correct accessor based on access mode. The
manual address bounds check is no longer necessary, since the accessor
helpers (get_user() / get_kernel_nofault()) do the right thing all by
themselves. As a bonus, by using the correct accessor, the open-coded
address bounds check is not needed anymore.

 [ bp: Massage commit message. ]

Fixes: eab0c6089b ("maccess: unify the probe kernel arch hooks")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/b91f7f92f3367d2d3a88eec3b09c6aab1b2dc8ef.1612924255.git.luto@kernel.org
2021-02-10 13:11:41 +01:00
Sean Christopherson ccd85d90ce KVM: SVM: Treat SVM as unsupported when running as an SEV guest
Don't let KVM load when running as an SEV guest, regardless of what
CPUID says.  Memory is encrypted with a key that is not accessible to
the host (L0), thus it's impossible for L0 to emulate SVM, e.g. it'll
see garbage when reading the VMCB.

Technically, KVM could decrypt all memory that needs to be accessible to
the L0 and use shadow paging so that L0 does not need to shadow NPT, but
exposing such information to L0 largely defeats the purpose of running as
an SEV guest.  This can always be revisited if someone comes up with a
use case for running VMs inside SEV guests.

Note, VMLOAD, VMRUN, etc... will also #GP on GPAs with C-bit set, i.e. KVM
is doomed even if the SEV guest is debuggable and the hypervisor is willing
to decrypt the VMCB.  This may or may not be fixed on CPUs that have the
SVME_ADDR_CHK fix.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210202212017.2486595-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-03 04:30:37 -05:00
Tom Lendacky 62a08a7193 x86/sev-es: Do not unroll string I/O for SEV-ES guests
Under the GHCB specification, SEV-ES guests can support string I/O.
The current #VC handler contains this support, so remove the need to
unroll kernel string I/O operations. This will reduce the number of #VC
exceptions generated as well as the number VM exits for the guest.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/3de04b5b638546ac75d42ba52307fe1a922173d3.1612203987.git.thomas.lendacky@amd.com
2021-02-02 16:25:05 +01:00
Andy Lutomirski 8ece53ef7f x86/vm86/32: Remove VM86_SCREEN_BITMAP support
The implementation was rather buggy.  It unconditionally marked PTEs
read-only, even for VM_SHARED mappings.  I'm not sure whether this is
actually a problem, but it certainly seems unwise.  More importantly, it
released the mmap lock before flushing the TLB, which could allow a racing
CoW operation to falsely believe that the underlying memory was not
writable.

I can't find any users at all of this mechanism, so just remove it.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Stas Sergeev <stsp2@yandex.ru>
Link: https://lkml.kernel.org/r/f3086de0babcab36f69949b5780bde851f719bc8.1611078018.git.luto@kernel.org
2021-01-21 20:08:53 +01:00
Tom Rix b86cb29287 x86: Remove definition of DEBUG
Defining DEBUG should only be done in development. So remove it.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20210114212827.47584-1-trix@redhat.com
2021-01-15 08:23:10 +01:00
Dan Williams d1c5246e08 x86/mm: Fix leak of pmd ptlock
Commit

  28ee90fe60 ("x86/mm: implement free pmd/pte page interfaces")

introduced a new location where a pmd was released, but neglected to
run the pmd page destructor. In fact, this happened previously for a
different pmd release path and was fixed by commit:

  c283610e44 ("x86, mm: do not leak page->ptl for pmd page tables").

This issue was hidden until recently because the failure mode is silent,
but commit:

  b2b29d6d01 ("mm: account PMD tables like PTE tables")

turns the failure mode into this signature:

 BUG: Bad page state in process lt-pmem-ns  pfn:15943d
 page:000000007262ed7b refcount:0 mapcount:-1024 mapping:0000000000000000 index:0x0 pfn:0x15943d
 flags: 0xaffff800000000()
 raw: 00affff800000000 dead000000000100 0000000000000000 0000000000000000
 raw: 0000000000000000 ffff913a029bcc08 00000000fffffbff 0000000000000000
 page dumped because: nonzero mapcount
 [..]
  dump_stack+0x8b/0xb0
  bad_page.cold+0x63/0x94
  free_pcp_prepare+0x224/0x270
  free_unref_page+0x18/0xd0
  pud_free_pmd_page+0x146/0x160
  ioremap_pud_range+0xe3/0x350
  ioremap_page_range+0x108/0x160
  __ioremap_caller.constprop.0+0x174/0x2b0
  ? memremap+0x7a/0x110
  memremap+0x7a/0x110
  devm_memremap+0x53/0xa0
  pmem_attach_disk+0x4ed/0x530 [nd_pmem]
  ? __devm_release_region+0x52/0x80
  nvdimm_bus_probe+0x85/0x210 [libnvdimm]

Given this is a repeat occurrence it seemed prudent to look for other
places where this destructor might be missing and whether a better
helper is needed. try_to_free_pmd_page() looks like a candidate, but
testing with setting up and tearing down pmd mappings via the dax unit
tests is thus far not triggering the failure.

As for a better helper pmd_free() is close, but it is a messy fit
due to requiring an @mm arg. Also, ___pmd_free_tlb() wants to call
paravirt_tlb_remove_table() instead of free_page(), so open-coded
pgtable_pmd_page_dtor() seems the best way forward for now.

Debugged together with Matthew Wilcox <willy@infradead.org>.

Fixes: 28ee90fe60 ("x86/mm: implement free pmd/pte page interfaces")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/160697689204.605323.17629854984697045602.stgit@dwillia2-desk3.amr.corp.intel.com
2021-01-05 11:40:23 +01:00
Lorenzo Stoakes 167dcfc08b x86/mm: Increase pgt_buf size for 5-level page tables
pgt_buf is used to allocate page tables on initial direct page mapping
which bootstraps the kernel into being able to allocate these before the
direct mapping makes further pages available.

INIT_PGD_PAGE_COUNT is set to 6 pages (doubled for KASLR) - 3 (PUD, PMD,
PTE) for the 1 MiB ISA mapping and 3 more for the first direct mapping
assignment in each case providing 2 MiB of address space.

This has not been updated for 5-level page tables which has an
additional P4D page table level above PUD.

In most instances, this will not have a material impact as the first
4 page levels allocated for the ISA mapping will provide sufficient
address space to encompass all further address mappings.

If the first direct mapping is within 512 GiB of the ISA mapping, only
a PMD and PTE needs to be added in the instance the kernel is using 4
KiB page tables (e.g. CONFIG_DEBUG_PAGEALLOC is enabled) and only a PMD
if the kernel can use 2 MiB pages (the first allocation is limited to
PMD_SIZE so a GiB page cannot be used there).

However, if the machine has more than 512 GiB of RAM and the kernel is
allocating 4 KiB page size, 3 further page tables are required.

If the machine has more than 256 TiB of RAM at 4 KiB or 2 MiB page size,
further 3 or 4 page tables are required respectively.

Update INIT_PGD_PAGE_COUNT to reflect this.

 [ bp: Sanitize text into passive voice without ambiguous personal pronouns. ]

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/20201215205641.34096-1-lstoakes@gmail.com
2021-01-04 18:07:50 +01:00
Linus Torvalds 007c74e16c Merge branch 'stable/for-linus-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb update from Konrad Rzeszutek Wilk:
 "A generic (but for right now engaged only with AMD SEV) mechanism to
  adjust a larger size SWIOTLB based on the total memory of the SEV
  guests which right now require the bounce buffer for interacting with
  the outside world.

  Normal knobs (swiotlb=XYZ) still work"

* 'stable/for-linus-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  x86,swiotlb: Adjust SWIOTLB bounce buffer size for SEV guests
2020-12-16 13:51:34 -08:00
Linus Torvalds ac73e3dc8a Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - a few random little subsystems

 - almost all of the MM patches which are staged ahead of linux-next
   material. I'll trickle to post-linux-next work in as the dependents
   get merged up.

Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits)
  mm: cleanup kstrto*() usage
  mm: fix fall-through warnings for Clang
  mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
  mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
  mm:backing-dev: use sysfs_emit in macro defining functions
  mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
  mm: use sysfs_emit for struct kobject * uses
  mm: fix kernel-doc markups
  zram: break the strict dependency from lzo
  zram: add stat to gather incompressible pages since zram set up
  zram: support page writeback
  mm/process_vm_access: remove redundant initialization of iov_r
  mm/zsmalloc.c: rework the list_add code in insert_zspage()
  mm/zswap: move to use crypto_acomp API for hardware acceleration
  mm/zswap: fix passing zero to 'PTR_ERR' warning
  mm/zswap: make struct kernel_param_ops definitions const
  userfaultfd/selftests: hint the test runner on required privilege
  userfaultfd/selftests: fix retval check for userfaultfd_open()
  userfaultfd/selftests: always dump something in modes
  userfaultfd: selftests: make __{s,u}64 format specifiers portable
  ...
2020-12-15 12:53:37 -08:00
Mike Rapoport 32a0de886e arch, mm: make kernel_page_present() always available
For architectures that enable ARCH_HAS_SET_MEMORY having the ability to
verify that a page is mapped in the kernel direct map can be useful
regardless of hibernation.

Add RISC-V implementation of kernel_page_present(), update its forward
declarations and stubs to be a part of set_memory API and remove ugly
ifdefery in inlcude/linux/mm.h around current declarations of
kernel_page_present().

Link: https://lkml.kernel.org/r/20201109192128.960-5-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:43 -08:00
Mike Rapoport 5d6ad668f3 arch, mm: restore dependency of __kernel_map_pages() on DEBUG_PAGEALLOC
The design of DEBUG_PAGEALLOC presumes that __kernel_map_pages() must
never fail.  With this assumption is wouldn't be safe to allow general
usage of this function.

Moreover, some architectures that implement __kernel_map_pages() have this
function guarded by #ifdef DEBUG_PAGEALLOC and some refuse to map/unmap
pages when page allocation debugging is disabled at runtime.

As all the users of __kernel_map_pages() were converted to use
debug_pagealloc_map_pages() it is safe to make it available only when
DEBUG_PAGEALLOC is set.

Link: https://lkml.kernel.org/r/20201109192128.960-4-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:43 -08:00
Linus Torvalds edd7ab7684 The new preemtible kmap_local() implementation:
- Consolidate all kmap_atomic() internals into a generic implementation
     which builds the base for the kmap_local() API and make the
     kmap_atomic() interface wrappers which handle the disabling/enabling of
     preemption and pagefaults.
 
   - Switch the storage from per-CPU to per task and provide scheduler
     support for clearing mapping when scheduling out and restoring them
     when scheduling back in.
 
   - Merge the migrate_disable/enable() code, which is also part of the
     scheduler pull request. This was required to make the kmap_local()
     interface available which does not disable preemption when a mapping
     is established. It has to disable migration instead to guarantee that
     the virtual address of the mapped slot is the same accross preemption.
 
   - Provide better debug facilities: guard pages and enforced utilization
     of the mapping mechanics on 64bit systems when the architecture allows
     it.
 
   - Provide the new kmap_local() API which can now be used to cleanup the
     kmap_atomic() usage sites all over the place. Most of the usage sites
     do not require the implicit disabling of preemption and pagefaults so
     the penalty on 64bit and 32bit non-highmem systems is removed and quite
     some of the code can be simplified. A wholesale conversion is not
     possible because some usage depends on the implicit side effects and
     some need to be cleaned up because they work around these side effects.
 
     The migrate disable side effect is only effective on highmem systems
     and when enforced debugging is enabled. On 64bit and 32bit non-highmem
     systems the overhead is completely avoided.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl/XyQwTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoUolD/9+R+BX96fGir+I8rG9dc3cbLw5meSi
 0I/Nq3PToZMs2Iqv50DsoaPYHHz/M6fcAO9LRIgsE9jRbnY93GnsBM0wU9Y8yQaT
 4wUzOG5WHaLDfqIkx/CN9coUl458oEiwOEbn79A2FmPXFzr7IpkufnV3ybGDwzwP
 p73bjMJMPPFrsa9ig87YiYfV/5IAZHi82PN8Cq1v4yNzgXRP3Tg6QoAuCO84ZnWF
 RYlrfKjcJ2xPdn+RuYyXolPtxr1hJQ0bOUpe4xu/UfeZjxZ7i1wtwLN9kWZe8CKH
 +x4Lz8HZZ5QMTQ9sCHOLtKzu2MceMcpISzoQH4/aFQCNMgLn1zLbS790XkYiQCuR
 ne9Cua+IqgYfGMG8cq8+bkU9HCNKaXqIBgPEKE/iHYVmqzCOqhW5Cogu4KFekf6V
 Wi7pyyUdX2en8BAWpk5NHc8de9cGcc+HXMq2NIcgXjVWvPaqRP6DeITERTZLJOmz
 XPxq5oPLGl7wdm7z+ICIaNApy8zuxpzb6sPLNcn7l5OeorViORlUu08AN8587wAj
 FiVjp6ZYomg+gyMkiNkDqFOGDH5TMENpOFoB0hNNEyJwwS0xh6CgWuwZcv+N8aPO
 HuS/P+tNANbD8ggT4UparXYce7YCtgOf3IG4GA3JJYvYmJ6pU+AZOWRoDScWq4o+
 +jlfoJhMbtx5Gg==
 =n71I
 -----END PGP SIGNATURE-----

Merge tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull kmap updates from Thomas Gleixner:
 "The new preemtible kmap_local() implementation:

   - Consolidate all kmap_atomic() internals into a generic
     implementation which builds the base for the kmap_local() API and
     make the kmap_atomic() interface wrappers which handle the
     disabling/enabling of preemption and pagefaults.

   - Switch the storage from per-CPU to per task and provide scheduler
     support for clearing mapping when scheduling out and restoring them
     when scheduling back in.

   - Merge the migrate_disable/enable() code, which is also part of the
     scheduler pull request. This was required to make the kmap_local()
     interface available which does not disable preemption when a
     mapping is established. It has to disable migration instead to
     guarantee that the virtual address of the mapped slot is the same
     across preemption.

   - Provide better debug facilities: guard pages and enforced
     utilization of the mapping mechanics on 64bit systems when the
     architecture allows it.

   - Provide the new kmap_local() API which can now be used to cleanup
     the kmap_atomic() usage sites all over the place. Most of the usage
     sites do not require the implicit disabling of preemption and
     pagefaults so the penalty on 64bit and 32bit non-highmem systems is
     removed and quite some of the code can be simplified. A wholesale
     conversion is not possible because some usage depends on the
     implicit side effects and some need to be cleaned up because they
     work around these side effects.

     The migrate disable side effect is only effective on highmem
     systems and when enforced debugging is enabled. On 64bit and 32bit
     non-highmem systems the overhead is completely avoided"

* tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  ARM: highmem: Fix cache_is_vivt() reference
  x86/crashdump/32: Simplify copy_oldmem_page()
  io-mapping: Provide iomap_local variant
  mm/highmem: Provide kmap_local*
  sched: highmem: Store local kmaps in task struct
  x86: Support kmap_local() forced debugging
  mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
  mm/highmem: Provide and use CONFIG_DEBUG_KMAP_LOCAL
  microblaze/mm/highmem: Add dropped #ifdef back
  xtensa/mm/highmem: Make generic kmap_atomic() work correctly
  mm/highmem: Take kmap_high_get() properly into account
  highmem: High implementation details and document API
  Documentation/io-mapping: Remove outdated blurb
  io-mapping: Cleanup atomic iomap
  mm/highmem: Remove the old kmap_atomic cruft
  highmem: Get rid of kmap_types.h
  xtensa/mm/highmem: Switch to generic kmap atomic
  sparc/mm/highmem: Switch to generic kmap atomic
  powerpc/mm/highmem: Switch to generic kmap atomic
  nds32/mm/highmem: Switch to generic kmap atomic
  ...
2020-12-14 18:35:53 -08:00
Linus Torvalds 405f868f13 - Remove all uses of TIF_IA32 and TIF_X32 and reclaim the two bits in the end
(Gabriel Krisman Bertazi)
 
 - All kinds of minor cleanups all over the tree.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl/XgtoACgkQEsHwGGHe
 VUqGuA/9GqN2zNQdhgRvAQ+FLZiOYK9MfXcoayfMq8T61VRPDBWaQRfVYKmfmEjS
 0l5OnYgZQ9n6vzqFy6pmgc/ix8Jr553dZp5NCamcOqjCTcuO/LwRRh+ZBeFSBTPi
 r2qFYKKRYvM7nbyUMm4WqvAakxJ18xsjNbIslr9Aqe8WtHBKKX3MOu8SOpFtGyXz
 aEc4rhsS45iZa5gTXhvOn73tr3yHGWU1rzyyAAAmDGTgAxRwsTna8v16C4+v+Bua
 Zg18Wiutj8ZjtFpzKJtGWGZoSBap3Jw2Ys64g42MBQUE56KY/99tQVo/SvbYvvlf
 PHWLH0f3rPNJ6J2qeKwhtNzPlEAH/6e416A1/6TVwsK+8pdfGmkfaQh2iDHLhJ5i
 CSwF61H44ZaE3pc1tHHbC5ALvydPlup7D4MKgztfq0mZ3OoV2Vg7dtyyr+Ybz72b
 G+Kl/tmyacQTXo0FiYbZKETo3/VfTdBXGyVax1rHkx3pt8zvhFg3kxb1TT/l/CoM
 eSTx53PtTdVtbGOq1CjnUm0FKlbh4+kLoNuo9DYKeXUQBs8PWOCZmL3wXmm4cqlZ
 mDZVWvll7CjToY8izzcE/AG279cWkgcL5Tcg7W7CR66+egfDdpuqOZ4tv4TyzoWq
 0J7WeNj+TAo98b7RA0Ux8LOlszRxS2ykuI6uB2MgwCaRMbbaQao=
 =lLiH
 -----END PGP SIGNATURE-----

Merge tag 'x86_cleanups_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cleanups from Borislav Petkov:
 "Another branch with a nicely negative diffstat, just the way I
  like 'em:

   - Remove all uses of TIF_IA32 and TIF_X32 and reclaim the two bits in
     the end (Gabriel Krisman Bertazi)

   - All kinds of minor cleanups all over the tree"

* tag 'x86_cleanups_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/ia32_signal: Propagate __user annotation properly
  x86/alternative: Update text_poke_bp() kernel-doc comment
  x86/PCI: Make a kernel-doc comment a normal one
  x86/asm: Drop unused RDPID macro
  x86/boot/compressed/64: Use TEST %reg,%reg instead of CMP $0,%reg
  x86/head64: Remove duplicate include
  x86/mm: Declare 'start' variable where it is used
  x86/head/64: Remove unused GET_CR2_INTO() macro
  x86/boot: Remove unused finalize_identity_maps()
  x86/uaccess: Document copy_from_user_nmi()
  x86/dumpstack: Make show_trace_log_lvl() static
  x86/mtrr: Fix a kernel-doc markup
  x86/setup: Remove unused MCA variables
  x86, libnvdimm/test: Remove COPY_MC_TEST
  x86: Reclaim TIF_IA32 and TIF_X32
  x86/mm: Convert mmu context ia32_compat into a proper flags field
  x86/elf: Use e_machine to check for x32/ia32 in setup_additional_pages()
  elf: Expose ELF header on arch_setup_additional_pages()
  x86/elf: Use e_machine to select start_thread for x32
  elf: Expose ELF header in compat_start_thread()
  ...
2020-12-14 13:45:26 -08:00
Linus Torvalds 54d794830f - A single improvement to check ident_pud_init()'s return value (Arvind Sankar)
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl/XUC8ACgkQEsHwGGHe
 VUoqig//YbNptsXveS0Kir4FUuWpLINbMGGfCekxlUItBzYFH3khqOcE4aiOfRB8
 TOx2QIFySiqJuTF4tnmwSs0QidHVchjVdD7+7f5jU2G8b/qzvU94+FdVQJJkTQa9
 pfOCxRr63ZjUdobPzSuEvZx9Wqr5kA1UpOsITxxx+rGR1M8HEA5dUYhSYgeoqFVI
 h7GgLSAfLkyeguTt2uHF8WOw0jgzkabw5CdiLAc/HwUh8Sde3ZdNCJizH5U636BF
 N+sNkQNjuo1t0lFAh9bjwTYq/0wy9ojqBYcXDDd2s1s62TuAOZ10u8dAW8+CeZuJ
 iC+7/j3QMulbrUeeOv48SkUkv+cMn+gcjcxFoHSEehVue9IciaoHasDACrB+0zBy
 pEZrFlyRGZyAjaXoiPQpsQ63/10W1zs+nFfP+IjM98O/I+ZawFfrjOI6x6qyWY3r
 DhskIaZ/Ha5nqzka1f502Xml54vBaeETQ7D8tQwco9wo3KyUPKXRLgHLiSiaUk/x
 FW/1hVC13mimn1n4eCB2sqwOKEFi8CfpLAbATrxmU8pRjIpcYK2B3mRWZBYUutEM
 uW1PdnnFI2680vKFrkWfWnqxSb4yLv/v5K4th5+8HzUyODWEq4hgSOdwZgxwEH9Y
 dQcfkiDbZRKEIoTiXDz4FFAlHeGMkldAT8YGYCBwQxX1DoCUvCg=
 =1LFY
 -----END PGP SIGNATURE-----

Merge tag 'x86_mm_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm update from Borislav Petkov:
 "A single improvement to check ident_pud_init()'s return value (Arvind
  Sankar)"

* tag 'x86_mm_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/ident_map: Check for errors from ident_pud_init()
2020-12-14 13:31:31 -08:00
Linus Torvalds 5583ff677b "Intel SGX is new hardware functionality that can be used by
applications to populate protected regions of user code and data called
 enclaves. Once activated, the new hardware protects enclave code and
 data from outside access and modification.
 
 Enclaves provide a place to store secrets and process data with those
 secrets. SGX has been used, for example, to decrypt video without
 exposing the decryption keys to nosy debuggers that might be used to
 subvert DRM. Software has generally been rewritten specifically to
 run in enclaves, but there are also projects that try to run limited
 unmodified software in enclaves."
 
 Most of the functionality is concentrated into arch/x86/kernel/cpu/sgx/
 except the addition of a new mprotect() hook to control enclave page
 permissions and support for vDSO exceptions fixup which will is used by
 SGX enclaves.
 
 All this work by Sean Christopherson, Jarkko Sakkinen and many others.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl/XTtMACgkQEsHwGGHe
 VUqxFw/+NZGf2b3CWPcrvwXCpkvSpIrqh1jQwyvkZyJ1gen7Vy8dkvf99h8+zQPI
 4wSArEyjhYJKAAmBNefLKi/Cs/bdkGzLlZyDGqtM641XRjf0xXIpQkOBb6UBa+Pv
 to8veQmVH2bBTM49qnd+H1wM6FzYvhTYCD8xr4HlLXtIfpP2CK2GvCb8s/4LifgD
 fTucZX9TFwLgVkWOHWHN0n8XMR2Fjb2YCrwjFMKyr/M2W+pPoOCTIt4PWDuXiOeG
 rFP7R4DT9jDg8ht5j2dHQT/Bo8TvTCB4Oj98MrX1TTgkSjLJySSMfyQg5EwNfSIa
 HC0lg/6qwAxnhWX7cCCBETNZ4aYDmz/dxcCSsLbomGP9nMaUgUy7qn5nNuNbJilb
 oCBsr8LDMzu1LJzmkduM8Uw6OINh+J8ICoVXaR5pS7gSZz/+vqIP/rK691AiqhJL
 QeMkI9gQ83jEXpr/AV7ABCjGCAeqELOkgravUyTDev24eEc0LyU0qENpgxqWSTca
 OvwSWSwNuhCKd2IyKZBnOmjXGwvncwX0gp1KxL9WuLkR6O8XldLAYmVCwVAOrIh7
 snRot8+3qNjELa65Nh5DapwLJrU24TRoKLHLgfWK8dlqrMejNtXKucQ574Np0feR
 p2hrNisOrtCwxAt7OAgWygw8agN6cJiY18onIsr4wSBm5H7Syb0=
 =k7tj
 -----END PGP SIGNATURE-----

Merge tag 'x86_sgx_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SGC support from Borislav Petkov:
 "Intel Software Guard eXtensions enablement. This has been long in the
  making, we were one revision number short of 42. :)

  Intel SGX is new hardware functionality that can be used by
  applications to populate protected regions of user code and data
  called enclaves. Once activated, the new hardware protects enclave
  code and data from outside access and modification.

  Enclaves provide a place to store secrets and process data with those
  secrets. SGX has been used, for example, to decrypt video without
  exposing the decryption keys to nosy debuggers that might be used to
  subvert DRM. Software has generally been rewritten specifically to run
  in enclaves, but there are also projects that try to run limited
  unmodified software in enclaves.

  Most of the functionality is concentrated into arch/x86/kernel/cpu/sgx/
  except the addition of a new mprotect() hook to control enclave page
  permissions and support for vDSO exceptions fixup which will is used
  by SGX enclaves.

  All this work by Sean Christopherson, Jarkko Sakkinen and many others"

* tag 'x86_sgx_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  x86/sgx: Return -EINVAL on a zero length buffer in sgx_ioc_enclave_add_pages()
  x86/sgx: Fix a typo in kernel-doc markup
  x86/sgx: Fix sgx_ioc_enclave_provision() kernel-doc comment
  x86/sgx: Return -ERESTARTSYS in sgx_ioc_enclave_add_pages()
  selftests/sgx: Use a statically generated 3072-bit RSA key
  x86/sgx: Clarify 'laundry_list' locking
  x86/sgx: Update MAINTAINERS
  Documentation/x86: Document SGX kernel architecture
  x86/sgx: Add ptrace() support for the SGX driver
  x86/sgx: Add a page reclaimer
  selftests/x86: Add a selftest for SGX
  x86/vdso: Implement a vDSO for Intel SGX enclave call
  x86/traps: Attempt to fixup exceptions in vDSO before signaling
  x86/fault: Add a helper function to sanitize error code
  x86/vdso: Add support for exception fixup in vDSO functions
  x86/sgx: Add SGX_IOC_ENCLAVE_PROVISION
  x86/sgx: Add SGX_IOC_ENCLAVE_INIT
  x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES
  x86/sgx: Add SGX_IOC_ENCLAVE_CREATE
  x86/sgx: Add an SGX misc driver interface
  ...
2020-12-14 13:14:57 -08:00
Ashish Kalra e998879d4f x86,swiotlb: Adjust SWIOTLB bounce buffer size for SEV guests
For SEV, all DMA to and from guest has to use shared (un-encrypted) pages.
SEV uses SWIOTLB to make this happen without requiring changes to device
drivers.  However, depending on the workload being run, the default 64MB
of it might not be enough and it may run out of buffers to use for DMA,
resulting in I/O errors and/or performance degradation for high
I/O workloads.

Adjust the default size of SWIOTLB for SEV guests using a
percentage of the total memory available to guest for the SWIOTLB buffers.

Adds a new sev_setup_arch() function which is invoked from setup_arch()
and it calls into a new swiotlb generic code function swiotlb_adjust_size()
to do the SWIOTLB buffer adjustment.

v5 fixed build errors and warnings as
Reported-by: kbuild test robot <lkp@intel.com>

Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Co-developed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2020-12-11 15:43:41 -05:00
Arvind Sankar 29ac40cbed x86/mm/mem_encrypt: Fix definition of PMD_FLAGS_DEC_WP
The PAT bit is in different locations for 4k and 2M/1G page table
entries.

Add a definition for _PAGE_LARGE_CACHE_MASK to represent the three
caching bits (PWT, PCD, PAT), similar to _PAGE_CACHE_MASK for 4k pages,
and use it in the definition of PMD_FLAGS_DEC_WP to get the correct PAT
index for write-protected pages.

Fixes: 6ebcb06071 ("x86/mm: Add support to encrypt the kernel in-place")
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20201111160946.147341-1-nivedita@alum.mit.edu
2020-12-10 12:28:06 +01:00
Andy Lutomirski a493d1ca1a x86/membarrier: Get rid of a dubious optimization
sync_core_before_usermode() had an incorrect optimization.  If the kernel
returns from an interrupt, it can get to usermode without IRET. It just has
to schedule to a different task in the same mm and do SYSRET.  Fortunately,
there were no callers of sync_core_before_usermode() that could have had
in_irq() or in_nmi() equal to true, because it's only ever called from the
scheduler.

While at it, clarify a related comment.

Fixes: 70216e18e5 ("membarrier: Provide core serializing command, *_SYNC_CORE")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/5afc7632be1422f91eaf7611aaaa1b5b8580a086.1607058304.git.luto@kernel.org
2020-12-09 09:37:42 +01:00
Dan Williams a927bd6ba9 mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports
The core-mm has a default __weak implementation of phys_to_target_node()
to mirror the weak definition of memory_add_physaddr_to_nid().  That
symbol is exported for modules.  However, while the export in
mm/memory_hotplug.c exported the symbol in the configuration cases of:

	CONFIG_NUMA_KEEP_MEMINFO=y
	CONFIG_MEMORY_HOTPLUG=y

...and:

	CONFIG_NUMA_KEEP_MEMINFO=n
	CONFIG_MEMORY_HOTPLUG=y

...it failed to export the symbol in the case of:

	CONFIG_NUMA_KEEP_MEMINFO=y
	CONFIG_MEMORY_HOTPLUG=n

Not only is that broken, but Christoph points out that the kernel should
not be exporting any __weak symbol, which means that
memory_add_physaddr_to_nid() example that phys_to_target_node() copied
is broken too.

Rework the definition of phys_to_target_node() and
memory_add_physaddr_to_nid() to not require weak symbols.  Move to the
common arch override design-pattern of an asm header defining a symbol
to replace the default implementation.

The only common header that all memory_add_physaddr_to_nid() producing
architectures implement is asm/sparsemem.h.  In fact, powerpc already
defines its memory_add_physaddr_to_nid() helper in sparsemem.h.
Double-down on that observation and define phys_to_target_node() where
necessary in asm/sparsemem.h.  An alternate consideration that was
discarded was to put this override in asm/numa.h, but that entangles
with the definition of MAX_NUMNODES relative to the inclusion of
linux/nodemask.h, and requires powerpc to grow a new header.

The dependency on NUMA_KEEP_MEMINFO for DEV_DAX_HMEM_DEVICES is invalid
now that the symbol is properly exported / stubbed in all combinations
of CONFIG_NUMA_KEEP_MEMINFO and CONFIG_MEMORY_HOTPLUG.

[dan.j.williams@intel.com: v4]
  Link: https://lkml.kernel.org/r/160461461867.1505359.5301571728749534585.stgit@dwillia2-desk3.amr.corp.intel.com
[dan.j.williams@intel.com: powerpc: fix create_section_mapping compile warning]
  Link: https://lkml.kernel.org/r/160558386174.2948926.2740149041249041764.stgit@dwillia2-desk3.amr.corp.intel.com

Fixes: a035b6bf86 ("mm/memory_hotplug: introduce default phys_to_target_node() implementation")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-22 10:48:22 -08:00
Lukas Bulwahn bab202ab87 x86/mm: Declare 'start' variable where it is used
It is not required to initialize the local variable start in
memory_map_top_down(), as the variable will be initialized in any path
before it is used.

make clang-analyzer on x86_64 tinyconfig reports:

  arch/x86/mm/init.c:612:15: warning: Although the value stored to 'start' \
  is used in the enclosing expression, the value is never actually read \
  from 'start' [clang-analyzer-deadcode.DeadStores]

Move the variable declaration into the loop, where it is used.

No code changed:

  # arch/x86/mm/init.o:

   text    data     bss     dec     hex filename
   7105    1424   26768   35297    89e1 init.o.before
   7105    1424   26768   35297    89e1 init.o.after

md5:
   a8d76c1bb5fce9cae251780a7ee7730f  init.o.before.asm
   a8d76c1bb5fce9cae251780a7ee7730f  init.o.after.asm

 [ bp: Massage. ]

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200928100004.25674-1-lukas.bulwahn@gmail.com
2020-11-20 12:49:00 +01:00
Sean Christopherson 334872a091 x86/traps: Attempt to fixup exceptions in vDSO before signaling
vDSO functions can now leverage an exception fixup mechanism similar to
kernel exception fixup.  For vDSO exception fixup, the initial user is
Intel's Software Guard Extensions (SGX), which will wrap the low-level
transitions to/from the enclave, i.e. EENTER and ERESUME instructions,
in a vDSO function and leverage fixup to intercept exceptions that would
otherwise generate a signal.  This allows the vDSO wrapper to return the
fault information directly to its caller, obviating the need for SGX
applications and libraries to juggle signal handlers.

Attempt to fixup vDSO exceptions immediately prior to populating and
sending signal information.  Except for the delivery mechanism, an
exception in a vDSO function should be treated like any other exception
in userspace, e.g. any fault that is successfully handled by the kernel
should not be directly visible to userspace.

Although it's debatable whether or not all exceptions are of interest to
enclaves, defer to the vDSO fixup to decide whether to do fixup or
generate a signal.  Future users of vDSO fixup, if there ever are any,
will undoubtedly have different requirements than SGX enclaves, e.g. the
fixup vs. signal logic can be made function specific if/when necessary.

Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Jethro Beekman <jethro@fortanix.com>
Link: https://lkml.kernel.org/r/20201112220135.165028-19-jarkko@kernel.org
2020-11-18 18:02:50 +01:00
Sean Christopherson cd072dab45 x86/fault: Add a helper function to sanitize error code
vDSO exception fixup is a replacement for signals in limited situations.
Signals and vDSO exception fixup need to provide similar information to
userspace, including the hardware error code.

That hardware error code needs to be sanitized.  For instance, if userspace
accesses a kernel address, the error code could indicate to userspace
whether the address had a Present=1 PTE.  That can leak information about
the kernel layout to userspace, which is bad.

The existing signal code does this sanitization, but fairly late in the
signal process.  The vDSO exception code runs before the sanitization
happens.

Move error code sanitization out of the signal code and into a helper.
Call the helper in the signal code.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Jethro Beekman <jethro@fortanix.com>
Link: https://lkml.kernel.org/r/20201112220135.165028-18-jarkko@kernel.org
2020-11-18 18:02:50 +01:00
Sean Christopherson 74faeee06d x86/mm: Signal SIGSEGV with PF_SGX
The x86 architecture has a set of page fault error codes.  These indicate
things like whether the fault occurred from a write, or whether it
originated in userspace.

The SGX hardware architecture has its own per-page memory management
metadata (EPCM) [*] and hardware which is separate from the normal x86 MMU.
The architecture has a new page fault error code: PF_SGX.  This new error
code bit is set whenever a page fault occurs as the result of the SGX MMU.

These faults occur for a variety of reasons.  For instance, an access
attempt to enclave memory from outside the enclave causes a PF_SGX fault.
PF_SGX would also be set for permission conflicts, such as if a write to an
enclave page occurs and the page is marked read-write in the x86 page
tables but is read-only in the EPCM.

These faults do not always indicate errors, though.  SGX pages are
encrypted with a key that is destroyed at hardware reset, including
suspend. Throwing a SIGSEGV allows user space software to react and recover
when these events occur.

Include PF_SGX in the PF error codes list and throw SIGSEGV when it is
encountered.

[*] Intel SDM: 36.5.1 Enclave Page Cache Map (EPCM)

 [ bp: Add bit 15 to the comment above enum x86_pf_error_code too. ]

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Jethro Beekman <jethro@fortanix.com>
Link: https://lkml.kernel.org/r/20201112220135.165028-7-jarkko@kernel.org
2020-11-17 14:36:13 +01:00
Thomas Gleixner 351191ad55 io-mapping: Cleanup atomic iomap
Switch the atomic iomap implementation over to kmap_local and stick the
preempt/pagefault mechanics into the generic code similar to the
kmap_atomic variants.

Rename the x86 map function in preparation for a non-atomic variant.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20201103095858.625310005@linutronix.de
2020-11-06 23:14:58 +01:00
Thomas Gleixner 157e118b55 x86/mm/highmem: Use generic kmap atomic implementation
Convert X86 to the generic kmap atomic implementation and make the
iomap_atomic() naming convention consistent while at it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201103095857.375127260@linutronix.de
2020-11-06 23:14:55 +01:00
Joerg Roedel c9f09539e1 x86/head/64: Check SEV encryption before switching to kernel page-table
When SEV is enabled, the kernel requests the C-bit position again from
the hypervisor to build its own page-table. Since the hypervisor is an
untrusted source, the C-bit position needs to be verified before the
kernel page-table is used.

Call sev_verify_cbit() before writing the CR3.

 [ bp: Massage. ]

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lkml.kernel.org/r/20201028164659.27002-5-joro@8bytes.org
2020-10-29 18:09:59 +01:00
Arvind Sankar 1fcd009102 x86/mm/ident_map: Check for errors from ident_pud_init()
Commit

  ea3b5e60ce ("x86/mm/ident_map: Add 5-level paging support")

added ident_p4d_init() to support 5-level paging, but this function
doesn't check and return errors from ident_pud_init().

For example, the decompressor stub uses this code to create an identity
mapping. If it runs out of pages while trying to allocate a PMD
pagetable, the error will be currently ignored.

Fix this to propagate errors.

 [ bp: Space out statements for better readability. ]

Fixes: ea3b5e60ce ("x86/mm/ident_map: Add 5-level paging support")
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20201027230648.1885111-1-nivedita@alum.mit.edu
2020-10-28 14:48:30 +01:00
Joe Perches 33def8498f treewide: Convert macro and uses of __section(foo) to __section("foo")
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25 14:51:49 -07:00
Linus Torvalds f9a705ad1c ARM:
- New page table code for both hypervisor and guest stage-2
 - Introduction of a new EL2-private host context
 - Allow EL2 to have its own private per-CPU variables
 - Support of PMU event filtering
 - Complete rework of the Spectre mitigation
 
 PPC:
 - Fix for running nested guests with in-kernel IRQ chip
 - Fix race condition causing occasional host hard lockup
 - Minor cleanups and bugfixes
 
 x86:
 - allow trapping unknown MSRs to userspace
 - allow userspace to force #GP on specific MSRs
 - INVPCID support on AMD
 - nested AMD cleanup, on demand allocation of nested SVM state
 - hide PV MSRs and hypercalls for features not enabled in CPUID
 - new test for MSR_IA32_TSC writes from host and guest
 - cleanups: MMU, CPUID, shared MSRs
 - LAPIC latency optimizations ad bugfixes
 
 For x86, also included in this pull request is a new alternative and
 (in the future) more scalable implementation of extended page tables
 that does not need a reverse map from guest physical addresses to
 host physical addresses.  For now it is disabled by default because
 it is still lacking a few of the existing MMU's bells and whistles.
 However it is a very solid piece of work and it is already available
 for people to hammer on it.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl+S8dsUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroM40Af+M46NJmuS5rcwFfybvK/c42KT6svX
 Co1NrZDwzSQ2mMy3WQzH9qeLvb+nbY4sT3n5BPNPNsT+aIDPOTDt//qJ2/Ip9UUs
 tRNea0MAR96JWLE7MSeeRxnTaQIrw/AAZC0RXFzZvxcgytXwdqBExugw4im+b+dn
 Dcz8QxX1EkwT+4lTm5HC0hKZAuo4apnK1QkqCq4SdD2QVJ1YE6+z7pgj4wX7xitr
 STKD6q/Yt/0ndwqS0GSGbyg0jy6mE620SN6isFRkJYwqfwLJci6KnqvEK67EcNMu
 qeE017K+d93yIVC46/6TfVHzLR/D1FpQ8LZ16Yl6S13OuGIfAWBkQZtPRg==
 =AD6a
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "For x86, there is a new alternative and (in the future) more scalable
  implementation of extended page tables that does not need a reverse
  map from guest physical addresses to host physical addresses.

  For now it is disabled by default because it is still lacking a few of
  the existing MMU's bells and whistles. However it is a very solid
  piece of work and it is already available for people to hammer on it.

  Other updates:

  ARM:
   - New page table code for both hypervisor and guest stage-2
   - Introduction of a new EL2-private host context
   - Allow EL2 to have its own private per-CPU variables
   - Support of PMU event filtering
   - Complete rework of the Spectre mitigation

  PPC:
   - Fix for running nested guests with in-kernel IRQ chip
   - Fix race condition causing occasional host hard lockup
   - Minor cleanups and bugfixes

  x86:
   - allow trapping unknown MSRs to userspace
   - allow userspace to force #GP on specific MSRs
   - INVPCID support on AMD
   - nested AMD cleanup, on demand allocation of nested SVM state
   - hide PV MSRs and hypercalls for features not enabled in CPUID
   - new test for MSR_IA32_TSC writes from host and guest
   - cleanups: MMU, CPUID, shared MSRs
   - LAPIC latency optimizations ad bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (232 commits)
  kvm: x86/mmu: NX largepage recovery for TDP MMU
  kvm: x86/mmu: Don't clear write flooding count for direct roots
  kvm: x86/mmu: Support MMIO in the TDP MMU
  kvm: x86/mmu: Support write protection for nesting in tdp MMU
  kvm: x86/mmu: Support disabling dirty logging for the tdp MMU
  kvm: x86/mmu: Support dirty logging for the TDP MMU
  kvm: x86/mmu: Support changed pte notifier in tdp MMU
  kvm: x86/mmu: Add access tracking for tdp_mmu
  kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMU
  kvm: x86/mmu: Allocate struct kvm_mmu_pages for all pages in TDP MMU
  kvm: x86/mmu: Add TDP MMU PF handler
  kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator arg
  kvm: x86/mmu: Support zapping SPTEs in the TDP MMU
  KVM: Cache as_id in kvm_memory_slot
  kvm: x86/mmu: Add functions to handle changed TDP SPTEs
  kvm: x86/mmu: Allocate and free TDP MMU roots
  kvm: x86/mmu: Init / Uninit the TDP MMU
  kvm: x86/mmu: Introduce tdp_iter
  KVM: mmu: extract spte.h and spte.c
  KVM: mmu: Separate updating a PTE from kvm_set_pte_rmapp
  ...
2020-10-23 11:17:56 -07:00
Vitaly Kuznetsov 66af4f5cb1 x86/kvm: Update the comment about asynchronous page fault in exc_page_fault()
KVM was switched to interrupt-based mechanism for 'page ready' event
delivery in Linux-5.8 (see commit 2635b5c4a0 ("KVM: x86: interrupt based
APF 'page ready' event delivery")) and #PF (ab)use for 'page ready' event
delivery was removed. Linux guest switched to this new mechanism
exclusively in 5.9 (see commit b1d405751c ("KVM: x86: Switch KVM guest to
using interrupts for page ready APF delivery")) so it is not possible to
get #PF for a 'page ready' event even when the guest is running on top
of an older KVM (APF mechanism won't be enabled). Update the comment in
exc_page_fault() to reflect the new reality.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20201002154313.1505327-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-21 17:36:31 -04:00
Linus Torvalds cf1d2b44f6 ACPI updates for 5.10-rc1
- Add support for generic initiator-only proximity domains to
    the ACPI NUMA code and the architectures using it (Jonathan
    Cameron).
 
  - Clean up some non-ACPICA code referring to debug facilities from
    ACPICA that are not actually used in there (Hanjun Guo).
 
  - Add new DPTF driver for the PCH FIVR participant (Srinivas
    Pandruvada).
 
  - Reduce overhead related to accessing GPE registers in ACPICA and
    the OS interface layer and make it possible to access GPE registers
    using logical addresses if they are memory-mapped (Rafael Wysocki).
 
  - Update the ACPICA code in the kernel to upstream revision 20200925
    including changes as follows:
    * Add predefined names from the SMBus sepcification (Bob Moore).
    * Update acpi_help UUID list (Bob Moore).
    * Return exceptions for string-to-integer conversions in iASL (Bob
      Moore).
    * Add a new "ALL <NameSeg>" debugger command (Bob Moore).
    * Add support for 64 bit risc-v compilation (Colin Ian King).
    * Do assorted cleanups (Bob Moore, Colin Ian King, Randy Dunlap).
 
  - Add new ACPI backlight whitelist entry for HP 635 Notebook (Alex
    Hung).
 
  - Move TPS68470 OpRegion driver to drivers/acpi/pmic/ and split out
    Kconfig and Makefile specific for ACPI PMIC (Andy Shevchenko).
 
  - Clean up the ACPI SoC driver for AMD SoCs (Hanjun Guo).
 
  - Add missing config_item_put() to fix refcount leak (Hanjun Guo).
 
  - Drop lefrover field from struct acpi_memory_device (Hanjun Guo).
 
  - Make the ACPI extlog driver check for RDMSR failures (Ben
    Hutchings).
 
  - Fix handling of lid state changes in the ACPI button driver when
    input device is closed (Dmitry Torokhov).
 
  - Fix several assorted build issues (Barnabás Pőcze, John Garry,
    Nathan Chancellor, Tian Tao).
 
  - Drop unused inline functions and reduce code duplication by using
    kobj_to_dev() in the NFIT parsing code (YueHaibing, Wang Qing).
 
  - Serialize tools/power/acpi Makefile (Thomas Renninger).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl+F4IkSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRx1gIQAIZrt09fquEIZhYulGZAkuYhSX2U/DZt
 poow5+TiGk36JNHlbZS19kZ3F0tJ1wA6CKSfF/bYyULxL+gYaUjdLXzv2kArTSAj
 nzDXQ2CystpySZI/sEkl4QjsMg0xuZlBhlnCfNHzJw049TgdsJHnxMkJXb8T90A+
 l2JKm2OpBkNvQGNpwd3djLg8xSDnHUmuevsWZPHDp92/fLMF9DUBk8dVuEwa0ndF
 hAUpWm+EL1tJQnhNwtfV/Akd9Ypqgk/7ROFWFHGDtHMZGnBjpyXZw68vHMX7SL6N
 Ej90GWGPHSJs/7Fsg4Hiaxxcph9WFNLPcpck5lVAMIrNHMKANjqQzCsmHavV/WTG
 STC9/qwJauA1EOjovlmlCFHctjKE/ya6Hm299WTlfBqB+Lu1L3oMR2CC+Uj0YfyG
 sv3264rJCsaSw610iwQOG807qHENopASO2q5DuKG0E9JpcaBUwn1N4qP5svvQciq
 4aA8Ma6xM/QHCO4CS0Se9C0+WSVtxWwOUichRqQmU4E6u1sXvKJxTeWo79rV7PAh
 L6BwoOxBLabEiyzpi6HPGs6DoKj/N6tOQenBh4ibdwpAwMtq7hIlBFa0bp19c2wT
 vx8F2Raa8vbQ2zZ1QEiPZnPLJUoy2DgaCtKJ6E0FTDXNs3VFlWgyhIUlIRqk5BS9
 OnAwVAUrTMkJ
 =feLU
 -----END PGP SIGNATURE-----

Merge tag 'acpi-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These add support for generic initiator-only proximity domains to the
  ACPI NUMA code and the architectures using it, clean up some
  non-ACPICA code referring to debug facilities from ACPICA, reduce the
  overhead related to accessing GPE registers, add a new DPTF (Dynamic
  Power and Thermal Framework) participant driver, update the ACPICA
  code in the kernel to upstream revision 20200925, add a new ACPI
  backlight whitelist entry, fix a few assorted issues and clean up some
  code.

  Specifics:

   - Add support for generic initiator-only proximity domains to the
     ACPI NUMA code and the architectures using it (Jonathan Cameron)

   - Clean up some non-ACPICA code referring to debug facilities from
     ACPICA that are not actually used in there (Hanjun Guo)

   - Add new DPTF driver for the PCH FIVR participant (Srinivas
     Pandruvada)

   - Reduce overhead related to accessing GPE registers in ACPICA and
     the OS interface layer and make it possible to access GPE registers
     using logical addresses if they are memory-mapped (Rafael Wysocki)

   - Update the ACPICA code in the kernel to upstream revision 20200925
     including changes as follows:
      + Add predefined names from the SMBus sepcification (Bob Moore)
      + Update acpi_help UUID list (Bob Moore)
      + Return exceptions for string-to-integer conversions in iASL (Bob
        Moore)
      + Add a new "ALL <NameSeg>" debugger command (Bob Moore)
      + Add support for 64 bit risc-v compilation (Colin Ian King)
      + Do assorted cleanups (Bob Moore, Colin Ian King, Randy Dunlap)

   - Add new ACPI backlight whitelist entry for HP 635 Notebook (Alex
     Hung)

   - Move TPS68470 OpRegion driver to drivers/acpi/pmic/ and split out
     Kconfig and Makefile specific for ACPI PMIC (Andy Shevchenko)

   - Clean up the ACPI SoC driver for AMD SoCs (Hanjun Guo)

   - Add missing config_item_put() to fix refcount leak (Hanjun Guo)

   - Drop lefrover field from struct acpi_memory_device (Hanjun Guo)

   - Make the ACPI extlog driver check for RDMSR failures (Ben
     Hutchings)

   - Fix handling of lid state changes in the ACPI button driver when
     input device is closed (Dmitry Torokhov)

   - Fix several assorted build issues (Barnabás Pőcze, John Garry,
     Nathan Chancellor, Tian Tao)

   - Drop unused inline functions and reduce code duplication by using
     kobj_to_dev() in the NFIT parsing code (YueHaibing, Wang Qing)

   - Serialize tools/power/acpi Makefile (Thomas Renninger)"

* tag 'acpi-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (64 commits)
  ACPICA: Update version to 20200925 Version 20200925
  ACPICA: Remove unnecessary semicolon
  ACPICA: Debugger: Add a new command: "ALL <NameSeg>"
  ACPICA: iASL: Return exceptions for string-to-integer conversions
  ACPICA: acpi_help: Update UUID list
  ACPICA: Add predefined names found in the SMBus sepcification
  ACPICA: Tree-wide: fix various typos and spelling mistakes
  ACPICA: Drop the repeated word "an" in a comment
  ACPICA: Add support for 64 bit risc-v compilation
  ACPI: button: fix handling lid state changes when input device closed
  tools/power/acpi: Serialize Makefile
  ACPI: scan: Replace ACPI_DEBUG_PRINT() with pr_debug()
  ACPI: memhotplug: Remove 'state' from struct acpi_memory_device
  ACPI / extlog: Check for RDMSR failure
  ACPI: Make acpi_evaluate_dsm() prototype consistent
  docs: mm: numaperf.rst Add brief description for access class 1.
  node: Add access1 class to represent CPU to memory characteristics
  ACPI: HMAT: Fix handling of changes from ACPI 6.2 to ACPI 6.3
  ACPI: Let ACPI know we support Generic Initiator Affinity Structures
  x86: Support Generic Initiator only proximity domains
  ...
2020-10-14 11:42:04 -07:00
Linus Torvalds da9803dfd3 This feature enhances the current guest memory encryption support
called SEV by also encrypting the guest register state, making the
 registers inaccessible to the hypervisor by en-/decrypting them on world
 switches. Thus, it adds additional protection to Linux guests against
 exfiltration, control flow and rollback attacks.
 
 With SEV-ES, the guest is in full control of what registers the
 hypervisor can access. This is provided by a guest-host exchange
 mechanism based on a new exception vector called VMM Communication
 Exception (#VC), a new instruction called VMGEXIT and a shared
 Guest-Host Communication Block which is a decrypted page shared between
 the guest and the hypervisor.
 
 Intercepts to the hypervisor become #VC exceptions in an SEV-ES guest so
 in order for that exception mechanism to work, the early x86 init code
 needed to be made able to handle exceptions, which, in itself, brings
 a bunch of very nice cleanups and improvements to the early boot code
 like an early page fault handler, allowing for on-demand building of the
 identity mapping. With that, !KASLR configurations do not use the EFI
 page table anymore but switch to a kernel-controlled one.
 
 The main part of this series adds the support for that new exchange
 mechanism. The goal has been to keep this as much as possibly
 separate from the core x86 code by concentrating the machinery in two
 SEV-ES-specific files:
 
  arch/x86/kernel/sev-es-shared.c
  arch/x86/kernel/sev-es.c
 
 Other interaction with core x86 code has been kept at minimum and behind
 static keys to minimize the performance impact on !SEV-ES setups.
 
 Work by Joerg Roedel and Thomas Lendacky and others.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl+FiKYACgkQEsHwGGHe
 VUqS5BAAlh5mKwtxXMyFyAIHa5tpsgDjbecFzy1UVmZyxN0JHLlM3NLmb+K52drY
 PiWjNNMi/cFMFazkuLFHuY0poBWrZml8zRS/mExKgUJC6EtguS9FQnRE9xjDBoWQ
 gOTSGJWEzT5wnFqo8qHwlC2CDCSF1hfL8ks3cUFW2tCWus4F9pyaMSGfFqD224rg
 Lh/8+arDMSIKE4uH0cm7iSuyNpbobId0l5JNDfCEFDYRigQZ6pZsQ9pbmbEpncs4
 rmjDvBA5eHDlNMXq0ukqyrjxWTX4ZLBOBvuLhpyssSXnnu2T+Tcxg09+ZSTyJAe0
 LyC9Wfo0v78JASXMAdeH9b1d1mRYNMqjvnBItNQoqweoqUXWz7kvgxCOp6b/G4xp
 cX5YhB6BprBW2DXL45frMRT/zX77UkEKYc5+0IBegV2xfnhRsjqQAQaWLIksyEaX
 nz9/C6+1Sr2IAv271yykeJtY6gtlRjg/usTlYpev+K0ghvGvTmuilEiTltjHrso1
 XAMbfWHQGSd61LNXofvx/GLNfGBisS6dHVHwtkayinSjXNdWxI6w9fhbWVjQ+y2V
 hOF05lmzaJSG5kPLrsFHFqm2YcxOmsWkYYDBHvtmBkMZSf5B+9xxDv97Uy9NETcr
 eSYk//TEkKQqVazfCQS/9LSm0MllqKbwNO25sl0Tw2k6PnheO2g=
 =toqi
 -----END PGP SIGNATURE-----

Merge tag 'x86_seves_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SEV-ES support from Borislav Petkov:
 "SEV-ES enhances the current guest memory encryption support called SEV
  by also encrypting the guest register state, making the registers
  inaccessible to the hypervisor by en-/decrypting them on world
  switches. Thus, it adds additional protection to Linux guests against
  exfiltration, control flow and rollback attacks.

  With SEV-ES, the guest is in full control of what registers the
  hypervisor can access. This is provided by a guest-host exchange
  mechanism based on a new exception vector called VMM Communication
  Exception (#VC), a new instruction called VMGEXIT and a shared
  Guest-Host Communication Block which is a decrypted page shared
  between the guest and the hypervisor.

  Intercepts to the hypervisor become #VC exceptions in an SEV-ES guest
  so in order for that exception mechanism to work, the early x86 init
  code needed to be made able to handle exceptions, which, in itself,
  brings a bunch of very nice cleanups and improvements to the early
  boot code like an early page fault handler, allowing for on-demand
  building of the identity mapping. With that, !KASLR configurations do
  not use the EFI page table anymore but switch to a kernel-controlled
  one.

  The main part of this series adds the support for that new exchange
  mechanism. The goal has been to keep this as much as possibly separate
  from the core x86 code by concentrating the machinery in two
  SEV-ES-specific files:

    arch/x86/kernel/sev-es-shared.c
    arch/x86/kernel/sev-es.c

  Other interaction with core x86 code has been kept at minimum and
  behind static keys to minimize the performance impact on !SEV-ES
  setups.

  Work by Joerg Roedel and Thomas Lendacky and others"

* tag 'x86_seves_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (73 commits)
  x86/sev-es: Use GHCB accessor for setting the MMIO scratch buffer
  x86/sev-es: Check required CPU features for SEV-ES
  x86/efi: Add GHCB mappings when SEV-ES is active
  x86/sev-es: Handle NMI State
  x86/sev-es: Support CPU offline/online
  x86/head/64: Don't call verify_cpu() on starting APs
  x86/smpboot: Load TSS and getcpu GDT entry before loading IDT
  x86/realmode: Setup AP jump table
  x86/realmode: Add SEV-ES specific trampoline entry point
  x86/vmware: Add VMware-specific handling for VMMCALL under SEV-ES
  x86/kvm: Add KVM-specific VMMCALL handling under SEV-ES
  x86/paravirt: Allow hypervisor-specific VMMCALL handling under SEV-ES
  x86/sev-es: Handle #DB Events
  x86/sev-es: Handle #AC Events
  x86/sev-es: Handle VMMCALL Events
  x86/sev-es: Handle MWAIT/MWAITX Events
  x86/sev-es: Handle MONITOR/MONITORX Events
  x86/sev-es: Handle INVD Events
  x86/sev-es: Handle RDPMC Events
  x86/sev-es: Handle RDTSC(P) Events
  ...
2020-10-14 10:21:34 -07:00
Mike Rapoport cc6de16805 memblock: use separate iterators for memory and reserved regions
for_each_memblock() is used to iterate over memblock.memory in a few
places that use data from memblock_region rather than the memory ranges.

Introduce separate for_each_mem_region() and
for_each_reserved_mem_region() to improve encapsulation of memblock
internals from its users.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>			[x86]
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>	[MIPS]
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>	[.clang-format]
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Emil Renner Berthing <kernel@esmil.dk>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20200818151634.14343-18-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:35 -07:00
Dan Williams a035b6bf86 mm/memory_hotplug: introduce default phys_to_target_node() implementation
In preparation to set a fallback value for dev_dax->target_node, introduce
generic fallback helpers for phys_to_target_node()

A generic implementation based on node-data or memblock was proposed, but
as noted by Mike:

    "Here again, I would prefer to add a weak default for
     phys_to_target_node() because the "generic" implementation is not really
     generic.

     The fallback to reserved ranges is x86 specfic because on x86 most of
     the reserved areas is not in memblock.memory. AFAIK, no other
     architecture does this."

The info message in the generic memory_add_physaddr_to_nid()
implementation is fixed up to properly reflect that
memory_add_physaddr_to_nid() communicates "online" node info and
phys_to_target_node() indicates "target / to-be-onlined" node info.

[akpm@linux-foundation.org: fix CONFIG_MEMORY_HOTPLUG=n build]
  Link: https://lkml.kernel.org/r/202008252130.7YrHIyMI%25lkp@intel.com

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Jia He <justin.he@arm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/159643097768.4062302.3135192588966888630.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:27 -07:00
Dan Williams 3b0d31011d x86/numa: add 'nohmat' option
Disable parsing of the HMAT for debug, to workaround broken platform
instances, or cases where it is otherwise not wanted.

[rdunlap@infradead.org: fix build when CONFIG_ACPI is not set]
  Link: https://lkml.kernel.org/r/70e5ee34-9809-a997-7b49-499e4be61307@infradead.org

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Jia He <justin.he@arm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/159643095540.4062302.732962081968036212.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:27 -07:00
Dan Williams 2dd57d3415 x86/numa: cleanup configuration dependent command-line options
Patch series "device-dax: Support sub-dividing soft-reserved ranges", v5.

The device-dax facility allows an address range to be directly mapped
through a chardev, or optionally hotplugged to the core kernel page
allocator as System-RAM.  It is the mechanism for converting persistent
memory (pmem) to be used as another volatile memory pool i.e.  the current
Memory Tiering hot topic on linux-mm.

In the case of pmem the nvdimm-namespace-label mechanism can sub-divide
it, but that labeling mechanism is not available / applicable to
soft-reserved ("EFI specific purpose") memory [3].  This series provides a
sysfs-mechanism for the daxctl utility to enable provisioning of
volatile-soft-reserved memory ranges.

The motivations for this facility are:

1/ Allow performance differentiated memory ranges to be split between
   kernel-managed and directly-accessed use cases.

2/ Allow physical memory to be provisioned along performance relevant
   address boundaries. For example, divide a memory-side cache [4] along
   cache-color boundaries.

3/ Parcel out soft-reserved memory to VMs using device-dax as a security
   / permissions boundary [5]. Specifically I have seen people (ab)using
   memmap=nn!ss (mark System-RAM as Persistent Memory) just to get the
   device-dax interface on custom address ranges. A follow-on for the VM
   use case is to teach device-dax to dynamically allocate 'struct page' at
   runtime to reduce the duplication of 'struct page' space in both the
   guest and the host kernel for the same physical pages.

[2]: http://lore.kernel.org/r/20200713160837.13774-11-joao.m.martins@oracle.com
[3]: http://lore.kernel.org/r/157309097008.1579826.12818463304589384434.stgit@dwillia2-desk3.amr.corp.intel.com
[4]: http://lore.kernel.org/r/154899811738.3165233.12325692939590944259.stgit@dwillia2-desk3.amr.corp.intel.com
[5]: http://lore.kernel.org/r/20200110190313.17144-1-joao.m.martins@oracle.com

This patch (of 23):

In preparation for adding a new numa= option clean up the existing ones to
avoid ifdefs in numa_setup(), and provide feedback when the option is
numa=fake= option is invalid due to kernel config.  The same does not need
to be done for numa=noacpi, since the capability is already hard disabled
at compile-time.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Jia He <justin.he@arm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/160106109960.30709.7379926726669669398.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/159643094279.4062302.17779410714418721328.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/159643094925.4062302.14979872973043772305.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:27 -07:00
Linus Torvalds c1b4ec85ee Do not sync vmalloc/ioremap mappings on x86-64 kernels.
Hopefully now without the bugs!
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl+Ej8oRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1jDeQ/9G1qMbMDef2XMIbQfHYbomDhzhZSZefZ4
 hWuW5brGuQY7SoOT2VQVlifIRVMj61kfSAO1z68vXIFgyNWyx+gCXCun8V8548R+
 E+/KFtPk4HlK1NAlSpz1wMlIe0OhW6fPLkAyty6w+iCAHORv6xPjZj6qhe38RzYS
 W9aEgPmL/13KylPndJGafRjmXbEgBZQWBchDcSW6TDOE/bwAeN+E7gghbGfXZWdc
 8+RJ0nasrfFKHZ4qB1rnF2KX/mNpK6gd6kNhLFadH0vFQ4Q/IQ34sk3T3muzV6N8
 x7Z85WTp5ewBJDPsJnoNs6tPKaKr88fVZl8+J81bjMFDCXkg0dDZRlIAG3X2miVV
 MuumqdBn34OvFTIFl8I4eydDCeIbZTKMAhveKx5I+dVxVX44ICJZNyVcfAtt96Fa
 Zq2NK3c52CsGwZWSqEQ1brSA1OKyZ1ny+ed1RJwYEFpKK1o8sha92L1MYhIkVcM4
 L/5vO1kH7e5fPbWxeQd4a5580JRzSD3/SHCqnd1GcY1xgJv9x73kcSbhY0xCMifi
 8SdZjNk2gzfKyCXzAcfVveYR3bmvG4LJyGRfc5arsxqHHg2eZD08SkakHUXxwMJ1
 C4vIdyGLwos5bWYPMNMPOy7HYS4Jm+MrzK3bZfz6Q6ezM7bGTPiU73HnXUJaLz1V
 7DuNKeS1i1Q=
 =tVAw
 -----END PGP SIGNATURE-----

Merge tag 'x86-mm-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm updates from Ingo Molnar:
 "Do not sync vmalloc/ioremap mappings on x86-64 kernels.

  Hopefully now without the bugs!"

* tag 'x86-mm-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/64: Update comment in preallocate_vmalloc_pages()
  x86/mm/64: Do not sync vmalloc/ioremap mappings
2020-10-12 15:02:38 -07:00
Linus Torvalds 8b6591fd0a * Cleanup different aspects of the UV code and start adding support for
the new UV5 class of systems, by Mike Travis.
 
 * Use a flexible array for a dynamically sized struct uv_rtc_timer_head,
 by Gustavo A. R. Silva.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl+EKuMACgkQEsHwGGHe
 VUp5pA//WHU9Xp3LGAL6FWaKGdiN4KA4+MZyl892LtWUy0RqPSSOP/hovyLfwOo8
 aXsaYdm2nlMXNBWNZd0CY+ZsEVV8XOJdbXiqi+Em1QINk3VLJM9rEN9QCALCPAkd
 kFdRC6ajJrgTFASa0agBToJiaNndPacZ2ndI8Bx+WIsbBsYx4oln3pCKtmeZNrNk
 bWnMTOK+sylILIScmhdgV/czMECAc4sMFF/W/rJdBpoA7duoa6yDycD7E3928o8H
 JtMc2wwBLXZSSh3YI7/Z80n7xopQgq3/WRqOjhNHVqRa5rR4ZnleQkXYw1MG2W0H
 Gk34aEcFA+M2xJZ2voL/YjngFEgMZG0HNg+AJJBX7K/+B3HvfTjWheTMMdaae7Wr
 iW4YFFxaJ5FoB2qFz8sZpln8tbniYxiwxJq9aESjwVqlEPoQ13ZTohAVXBJq+CsZ
 NufRJyY7bB5SoDiIucWNdAnJ4bUQDs+UouUqrSORtPqQg/+gJ17krZxQY+oST1I+
 BDmAInBzcdScyjAKui7+csgSWW4lgHDUzqYGnFogcpvJc3s9HnqebTNqTwQQvrDM
 e8VbuH2X3z5/xgbtE9W3ND3Rf+4CLTMbd6J8SKAceI9sQ1ZOZzLZlJU4TQCbXXoW
 vSI5Gv9B3AlI4PGIphdt4M3Sm78fG11PMwuUQEO3WSLjOt5amrM=
 =llxK
 -----END PGP SIGNATURE-----

Merge tag 'x86_platform_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 platform updates from Borislav Petkov:

 - Cleanup different aspects of the UV code and start adding support for
   the new UV5 class of systems (Mike Travis)

 - Use a flexible array for a dynamically sized struct uv_rtc_timer_head
   (Gustavo A. R. Silva)

* tag 'x86_platform_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform/uv: Update Copyrights to conform to HPE standards
  x86/platform/uv: Update for UV5 NMI MMR changes
  x86/platform/uv: Update UV5 TSC checking
  x86/platform/uv: Update node present counting
  x86/platform/uv: Update UV5 MMR references in UV GRU
  x86/platform/uv: Adjust GAM MMR references affected by UV5 updates
  x86/platform/uv: Update MMIOH references based on new UV5 MMRs
  x86/platform/uv: Add and decode Arch Type in UVsystab
  x86/platform/uv: Add UV5 direct references
  x86/platform/uv: Update UV MMRs for UV5
  drivers/misc/sgi-xp: Adjust references in UV kernel modules
  x86/platform/uv: Remove SCIR MMR references for UV systems
  x86/platform/uv: Remove UV BAU TLB Shootdown Handler
  x86/uv/time: Use a flexible array in struct uv_rtc_timer_head
2020-10-12 10:31:18 -07:00
Linus Torvalds 92a0610b6a * Add support for hardware-enforced cache coherency on AMD which
obviates the need to flush cachelines before changing the PTE encryption
 bit, by Krish Sadhukhan.
 
 * Add Centaur initialization support for families >= 7, by Tony W
 Wang-oc.
 
 * Add a feature flag for, and expose TSX suspend load tracking feature
 to KVM, by Cathy Zhang.
 
 * Emulate SLDT and STR so that windows programs don't crash on UMIP
 machines, by Brendan Shanks and Ricardo Neri.
 
 * Use the new SERIALIZE insn on Intel hardware which supports it, by
 Ricardo Neri.
 
 * Misc cleanups and fixes.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl+EKA4ACgkQEsHwGGHe
 VUq9/RAAtneeyhaM3Erjj+4gLi383ml7n8hlAixZ7x1T5mkV7B5rKtNQ99AYQTbp
 lbA7qu5mfsEqKeu2WY13IMqHKgfgGXPPUumCTYjgQlC6UoSAMjgtGGCDodqBE8i5
 iIq6gp59t4aMn1ltkzNMS0hLGX0i3xA6cBHPB6EVdJhQgaX4oVVs1dL8IbXumj3q
 NX5qIcaTN/f/IC3EZuCDwZGKUpRF+PWTbD+k02jfhS2crvG/LHJgtisQJ1Eu/ccz
 yKfiwCBYS7FcuDTxiJDchz1sXD25dgBmBG26voIukSIPbysAPF7O1MULGvKsztFV
 W/6+VMC+KGUs0ACQHhFl5ALXA73zAJskjzNzRRuduYM0Mr2yAckVet2usicnt/Cp
 lpmvOpeCjDTPuBQTs0cR9TWjXFeinUkQJOAEcqv9Wh1OKQShZUAJ1jpHwZiDCnhY
 kzOhq9GAgKNXxcqcTQD8mIap2/GKIppIxAVb7vPxDQfUhUz/60o0eF3cMkeaa216
 31Bnf4h+XtJPoJkDOhI8XrPLw6c3KRWP3i3IoBj+raLiylwzzrIczf/7CBgHoIsa
 fEwuM0PUDVurY38VMRlj1dMFBSFw8U7JqKYyvXKwB3KFeyX7SGZDLmdlvhsRTq20
 HJepCVldKZvjDq1zvRFyx/TsZQnoDHsIyv5lAC/EKE3S0/XRg2c=
 =zXC1
 -----END PGP SIGNATURE-----

Merge tag 'x86_cpu_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpu updates from Borislav Petkov:

 - Add support for hardware-enforced cache coherency on AMD which
   obviates the need to flush cachelines before changing the PTE
   encryption bit (Krish Sadhukhan)

 - Add Centaur initialization support for families >= 7 (Tony W Wang-oc)

 - Add a feature flag for, and expose TSX suspend load tracking feature
   to KVM (Cathy Zhang)

 - Emulate SLDT and STR so that windows programs don't crash on UMIP
   machines (Brendan Shanks and Ricardo Neri)

 - Use the new SERIALIZE insn on Intel hardware which supports it
   (Ricardo Neri)

 - Misc cleanups and fixes

* tag 'x86_cpu_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  KVM: SVM: Don't flush cache if hardware enforces cache coherency across encryption domains
  x86/mm/pat: Don't flush cache if hardware enforces cache coherency across encryption domnains
  x86/cpu: Add hardware-enforced cache coherency as a CPUID feature
  x86/cpu/centaur: Add Centaur family >=7 CPUs initialization support
  x86/cpu/centaur: Replace two-condition switch-case with an if statement
  x86/kvm: Expose TSX Suspend Load Tracking feature
  x86/cpufeatures: Enumerate TSX suspend load address tracking instructions
  x86/umip: Add emulation/spoofing for SLDT and STR instructions
  x86/cpu: Fix typos and improve the comments in sync_core()
  x86/cpu: Use XGETBV and XSETBV mnemonics in fpu/internal.h
  x86/cpu: Use SERIALIZE in sync_core() when available
2020-10-12 10:24:40 -07:00
Linus Torvalds ca1b66922a * Extend the recovery from MCE in kernel space also to processes which
encounter an MCE in kernel space but while copying from user memory by
 sending them a SIGBUS on return to user space and umapping the faulty
 memory, by Tony Luck and Youquan Song.
 
 * memcpy_mcsafe() rework by splitting the functionality into
 copy_mc_to_user() and copy_mc_to_kernel(). This, as a result, enables
 support for new hardware which can recover from a machine check
 encountered during a fast string copy and makes that the default and
 lets the older hardware which does not support that advance recovery,
 opt in to use the old, fragile, slow variant, by Dan Williams.
 
 * New AMD hw enablement, by Yazen Ghannam and Akshay Gupta.
 
 * Do not use MSR-tracing accessors in #MC context and flag any fault
 while accessing MCA architectural MSRs as an architectural violation
 with the hope that such hw/fw misdesigns are caught early during the hw
 eval phase and they don't make it into production.
 
 * Misc fixes, improvements and cleanups, as always.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAl+EIpUACgkQEsHwGGHe
 VUouoBAAgwb+NkWZtIqGImV4f+LOyFjhTR/r/7ZyiijXdbhOIuAdc/jQM31mQxug
 sX2jxaRYnf1n6SLA0ggX99gwr2deRQ/hsNf5Abw55GC+Z1dOxpGL0k59A3ELl1IR
 H9KYmCAFQIHvzfk38qcdND73XHcgthQoXFBOG9wAPAdgDWnaiWt6lcLAq8OiJTmp
 D8pInAYhcnL8YXwMGyQQ1KkFn9HwydoWDsK5Ff2shaw2/+dMQqd1zetenbVtjhLb
 iNYGvV7Bi/RQ8PyMbzmtTWa4kwQJAHC2gptkGxty//2ADGVBbqUQdqF9TjIWCNy5
 V6Ldv5zo0/1s7DOzji3htzqkSs/K1Ea6d2LtZjejkJipHKV5x068UC6Fu+PlfS2D
 VZfcICeapU4G2F3Zvks2DlZ7dVTbHCvoI78Qi7bBgczPUVmk6iqah4xuQaiHyBJc
 kTFDA4Nnf/026GpoWRiFry9vqdnHBZyLet5A6Y+SoWF0FbhYnCVPpq4MnussYoav
 lUIi9ZZav6X2RZp9DDM1f9d5xubtKq0DKt93wvzqAhjK0T2DikckJ+riOYkI6N8t
 fHCBNUkdfgyMzJUTBPAzYQ7RmjbjKWJi7xWP0oz6+GqOJkQfSTVC5/2yEffbb3ya
 whYRS6iklbl7yshzaOeecXsZcAeK2oGPfoHg34WkHFgXdF5mNgA=
 =u1Wg
 -----END PGP SIGNATURE-----

Merge tag 'ras_updates_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS updates from Borislav Petkov:

 - Extend the recovery from MCE in kernel space also to processes which
   encounter an MCE in kernel space but while copying from user memory
   by sending them a SIGBUS on return to user space and umapping the
   faulty memory, by Tony Luck and Youquan Song.

 - memcpy_mcsafe() rework by splitting the functionality into
   copy_mc_to_user() and copy_mc_to_kernel(). This, as a result, enables
   support for new hardware which can recover from a machine check
   encountered during a fast string copy and makes that the default and
   lets the older hardware which does not support that advance recovery,
   opt in to use the old, fragile, slow variant, by Dan Williams.

 - New AMD hw enablement, by Yazen Ghannam and Akshay Gupta.

 - Do not use MSR-tracing accessors in #MC context and flag any fault
   while accessing MCA architectural MSRs as an architectural violation
   with the hope that such hw/fw misdesigns are caught early during the
   hw eval phase and they don't make it into production.

 - Misc fixes, improvements and cleanups, as always.

* tag 'ras_updates_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Allow for copy_mc_fragile symbol checksum to be generated
  x86/mce: Decode a kernel instruction to determine if it is copying from user
  x86/mce: Recover from poison found while copying from user space
  x86/mce: Avoid tail copy when machine check terminated a copy from user
  x86/mce: Add _ASM_EXTABLE_CPY for copy user access
  x86/mce: Provide method to find out the type of an exception handler
  x86/mce: Pass pointer to saved pt_regs to severity calculation routines
  x86/copy_mc: Introduce copy_mc_enhanced_fast_string()
  x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()
  x86/mce: Drop AMD-specific "DEFERRED" case from Intel severity rule list
  x86/mce: Add Skylake quirk for patrol scrub reported errors
  RAS/CEC: Convert to DEFINE_SHOW_ATTRIBUTE()
  x86/mce: Annotate mce_rd/wrmsrl() with noinstr
  x86/mce/dev-mcelog: Do not update kflags on AMD systems
  x86/mce: Stop mce_reign() from re-computing severity for every CPU
  x86/mce: Make mce_rdmsrl() panic on an inaccessible MSR
  x86/mce: Increase maximum number of banks to 64
  x86/mce: Delay clearing IA32_MCG_STATUS to the end of do_machine_check()
  x86/MCE/AMD, EDAC/mce_amd: Remove struct smca_hwid.xec_bitmap
  RAS/CEC: Fix cec_init() prototype
2020-10-12 10:14:38 -07:00
Tony Luck 3006381013 x86/mce: Decode a kernel instruction to determine if it is copying from user
All instructions copying data between kernel and user memory
are tagged with either _ASM_EXTABLE_UA or _ASM_EXTABLE_CPY
entries in the exception table. ex_fault_handler_type() returns
EX_HANDLER_UACCESS for both of these.

Recovery is only possible when the machine check was triggered
on a read from user memory. In this case the same strategy for
recovery applies as if the user had made the access in ring3. If
the fault was in kernel memory while copying to user there is no
current recovery plan.

For MOV and MOVZ instructions a full decode of the instruction
is done to find the source address. For MOVS instructions
the source address is in the %rsi register. The function
fault_in_kernel_space() determines whether the source address is
kernel or user, upgrade it from "static" so it can be used here.

Co-developed-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-7-tony.luck@intel.com
2020-10-07 11:32:40 +02:00
Youquan Song 278b917f8c x86/mce: Add _ASM_EXTABLE_CPY for copy user access
_ASM_EXTABLE_UA is a general exception entry to record the exception fixup
for all exception spots between kernel and user space access.

To enable recovery from machine checks while coping data from user
addresses it is necessary to be able to distinguish the places that are
looping copying data from those that copy a single byte/word/etc.

Add a new macro _ASM_EXTABLE_CPY and use it in place of _ASM_EXTABLE_UA
in the copy functions.

Record the exception reason number to regs->ax at
ex_handler_uaccess which is used to check MCE triggered.

The new fixup routine ex_handler_copy() is almost an exact copy of
ex_handler_uaccess() The difference is that it sets regs->ax to the trap
number. Following patches use this to avoid trying to copy remaining
bytes from the tail of the copy and possibly hitting the poison again.

New mce.kflags bit MCE_IN_KERNEL_COPYIN will be used by mce_severity()
calculation to indicate that a machine check is recoverable because the
kernel was copying from user space.

Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-4-tony.luck@intel.com
2020-10-07 11:19:11 +02:00
Tony Luck a05d54c41e x86/mce: Provide method to find out the type of an exception handler
Avoid a proliferation of ex_has_*_handler() functions by having just
one function that returns the type of the handler (if any).

Drop the __visible attribute for this function. It is not called
from assembler so the attribute is not necessary.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-3-tony.luck@intel.com
2020-10-07 11:08:59 +02:00
Mike Travis 39297dde73 x86/platform/uv: Remove UV BAU TLB Shootdown Handler
The Broadcast Assist Unit (BAU) TLB shootdown handler is being rewritten
to become the UV BAU APIC driver. It is designed to speed up sending
IPIs to selective CPUs within the system. Remove the current TLB
shutdown handler (tlb_uv.c) file and a couple of kernel hooks in the
interim.

Signed-off-by: Mike Travis <mike.travis@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Link: https://lkml.kernel.org/r/20201005203929.148656-2-mike.travis@hpe.com
2020-10-07 08:45:39 +02:00
Jonathan Cameron 73bf7382de x86: Support Generic Initiator only proximity domains
In common with memoryless domains only register GI domains
if the proximity node is not online. If a domain is already
a memory containing domain, or a memoryless domain there is
nothing to do just because it also contains a Generic Initiator.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-02 18:51:57 +02:00
Krish Sadhukhan 75d1cc0e05 x86/mm/pat: Don't flush cache if hardware enforces cache coherency across encryption domnains
In some hardware implementations, coherency between the encrypted and
unencrypted mappings of the same physical page is enforced. In such a
system, it is not required for software to flush the page from all CPU
caches in the system prior to changing the value of the C-bit for the
page. So check that bit before flushing the cache.

 [ bp: Massage commit message. ]

Suggested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200917212038.5090-3-krish.sadhukhan@oracle.com
2020-09-18 10:47:00 +02:00
Joerg Roedel 6b27edd74a x86/dumpstack/64: Add noinstr version of get_stack_info()
The get_stack_info() functionality is needed in the entry code for the
#VC exception handler. Provide a version of it in the .text.noinstr
section which can be called safely from there.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907131613.12703-45-joro@8bytes.org
2020-09-09 11:33:19 +02:00
Joerg Roedel 1aa9aa8ee5 x86/sev-es: Setup GHCB-based boot #VC handler
Add the infrastructure to handle #VC exceptions when the kernel runs on
virtual addresses and has mapped a GHCB. This handler will be used until
the runtime #VC handler takes over.

Since the handler runs very early, disable instrumentation for sev-es.c.

 [ bp: Make vc_ghcb_invalidate() __always_inline so that it can be
   inlined in noinstr functions like __sev_es_nmi_complete(). ]

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200908123816.GB3764@8bytes.org
2020-09-09 11:32:27 +02:00
Joerg Roedel c685eb0c12 x86/sev-es: Print SEV-ES info into the kernel log
Refactor the message printed to the kernel log which indicates whether
SEV or SME, etc is active. This will scale better in the future when
more memory encryption features might be added. Also add SEV-ES to the
list of features.

 [ bp: Massage. ]

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200907131613.12703-38-joro@8bytes.org
2020-09-08 00:38:01 +02:00
Joerg Roedel b57de6cd16 x86/sev-es: Add SEV-ES Feature Detection
Add a sev_es_active() function for checking whether SEV-ES is enabled.
Also cache the value of MSR_AMD64_SEV at boot to speed up the feature
checking in the running code.

 [ bp: Remove "!!" in sev_active() too. ]

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200907131613.12703-37-joro@8bytes.org
2020-09-07 23:00:20 +02:00
Huang Ying ccae0f36d5 x86, fakenuma: Fix invalid starting node ID
Commit:

  cc9aec03e5 ("x86/numa_emulation: Introduce uniform split capability")

uses "-1" as the starting node ID, which causes the strange kernel log as
follows, when "numa=fake=32G" is added to the kernel command line:

    Faking node -1 at [mem 0x0000000000000000-0x0000000893ffffff] (35136MB)
    Faking node 0 at [mem 0x0000001840000000-0x000000203fffffff] (32768MB)
    Faking node 1 at [mem 0x0000000894000000-0x000000183fffffff] (64192MB)
    Faking node 2 at [mem 0x0000002040000000-0x000000283fffffff] (32768MB)
    Faking node 3 at [mem 0x0000002840000000-0x000000303fffffff] (32768MB)

And finally the kernel crashes:

    BUG: Bad page state in process swapper  pfn:00011
    page:(____ptrval____) refcount:0 mapcount:1 mapping:(____ptrval____) index:0x55cd7e44b270 pfn:0x11
    failed to read mapping contents, not a valid kernel address?
    flags: 0x5(locked|uptodate)
    raw: 0000000000000005 000055cd7e44af30 000055cd7e44af50 0000000100000006
    raw: 000055cd7e44b270 000055cd7e44b290 0000000000000000 000055cd7e44b510
    page dumped because: page still charged to cgroup
    page->mem_cgroup:000055cd7e44b510
    Modules linked in:
    CPU: 0 PID: 0 Comm: swapper Not tainted 5.9.0-rc2 #1
    Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019
    Call Trace:
     dump_stack+0x57/0x80
     bad_page.cold+0x63/0x94
     __free_pages_ok+0x33f/0x360
     memblock_free_all+0x127/0x195
     mem_init+0x23/0x1f5
     start_kernel+0x219/0x4f5
     secondary_startup_64+0xb6/0xc0

Fix this bug via using 0 as the starting node ID.  This restores the
original behavior before cc9aec03e5.

[ mingo: Massaged the changelog. ]

Fixes: cc9aec03e5 ("x86/numa_emulation: Introduce uniform split capability")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200904061047.612950-1-ying.huang@intel.com
2020-09-04 08:56:13 +02:00
Joerg Roedel 4819e15f74 x86/mm/32: Bring back vmalloc faulting on x86_32
One can not simply remove vmalloc faulting on x86-32. Upstream

	commit: 7f0a002b5a ("x86/mm: remove vmalloc faulting")

removed it on x86 alltogether because previously the
arch_sync_kernel_mappings() interface was introduced. This interface
added synchronization of vmalloc/ioremap page-table updates to all
page-tables in the system at creation time and was thought to make
vmalloc faulting obsolete.

But that assumption was incredibly naive.

It turned out that there is a race window between the time the vmalloc
or ioremap code establishes a mapping and the time it synchronizes
this change to other page-tables in the system.

During this race window another CPU or thread can establish a vmalloc
mapping which uses the same intermediate page-table entries (e.g. PMD
or PUD) and does no synchronization in the end, because it found all
necessary mappings already present in the kernel reference page-table.

But when these intermediate page-table entries are not yet
synchronized, the other CPU or thread will continue with a vmalloc
address that is not yet mapped in the page-table it currently uses,
causing an unhandled page fault and oops like below:

	BUG: unable to handle page fault for address: fe80c000
	#PF: supervisor write access in kernel mode
	#PF: error_code(0x0002) - not-present page
	*pde = 33183067 *pte = a8648163
	Oops: 0002 [#1] SMP
	CPU: 1 PID: 13514 Comm: cve-2017-17053 Tainted: G
	...
	Call Trace:
	 ldt_dup_context+0x66/0x80
	 dup_mm+0x2b3/0x480
	 copy_process+0x133b/0x15c0
	 _do_fork+0x94/0x3e0
	 __ia32_sys_clone+0x67/0x80
	 __do_fast_syscall_32+0x3f/0x70
	 do_fast_syscall_32+0x29/0x60
	 do_SYSENTER_32+0x15/0x20
	 entry_SYSENTER_32+0x9f/0xf2
	EIP: 0xb7eef549

So the arch_sync_kernel_mappings() interface is racy, but removing it
would mean to re-introduce the vmalloc_sync_all() interface, which is
even more awful. Keep arch_sync_kernel_mappings() in place and catch
the race condition in the page-fault handler instead.

Do a partial revert of above commit to get vmalloc faulting on x86-32
back in place.

Fixes: 7f0a002b5a ("x86/mm: remove vmalloc faulting")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200902155904.17544-1-joro@8bytes.org
2020-09-03 11:23:35 +02:00
Linus Torvalds b69bea8a65 A set of fixes for lockdep, tracing and RCU:
- Prevent recursion by using raw_cpu_* operations
 
   - Fixup the interrupt state in the cpu idle code to be consistent
 
   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections
 
   - Move trace_cpu_idle() into generic code so it's called before RCU goes
     idle.
 
   - Handle raw_local_irq* vs. local_irq* operations correctly
 
   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl9L5qETHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoV/NEADG+h02tj2I4gP7IQ3nVodEzS1+odPI
 orabY5ggH0kn4YIhPB4UtOd5zKZjr3FJs9wEhyhQpV6ZhvFfgaIKiYqfg+Q81aMO
 /BXrfh6jBD2Hu7gaPBnVdkKeh1ehl+w0PhTeJhPBHEEvbGeLUYWwyPNlaKz//VQl
 XCWl7e7o/Uw2UyJ469SCx3z+M2DMNqwdMys/zcqvTLiBdLNCwp4TW5ACzEA0rfHh
 Pepu3eIKnMURyt82QanrOATvT2io9pOOaUh59zeKi2WM8ikwKd/Eho2kXYng6GvM
 GzX4Kn13MsNobZXf9BhqEGICdRkaJqLsXlmBNmbJdSTCn5W2lLZqu2wCEp5VZHCc
 XwMbey8ek+BRskJMqAV4oq2GA8Om9KEYWOOdixyOG0UJCiW5qDowuDYBXTLV7FWj
 XhzLGuHpUF9eKLKokJ7ideLaDcpzwYjHr58pFLQrqPwmjVKWguLeYMg5BhhTiEuV
 wNfiLIGdMNsCpYKhnce3o9paV8+hy1ZveWhNy+/4HaDLoEwI2T62i8R7xxbrcWMg
 sgdAiQG+kVLwSJ13bN+Cz79uLYTIbqGaZHtOXmeIT3jSxBjx5RlXfzocwTHSYrNk
 GuLYHd7+QaemN49Rrf4bPR16Db7ifL32QkUtLBTBLcnos9jM+fcl+BWyqYRxhgDv
 xzDS+vfK8DvRiA==
 =Hgt6
 -----END PGP SIGNATURE-----

Merge tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "A set of fixes for lockdep, tracing and RCU:

   - Prevent recursion by using raw_cpu_* operations

   - Fixup the interrupt state in the cpu idle code to be consistent

   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections

   - Move trace_cpu_idle() into generic code so it's called before RCU
     goes idle.

   - Handle raw_local_irq* vs. local_irq* operations correctly

   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent"

* tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep,trace: Expose tracepoints
  lockdep: Only trace IRQ edges
  mips: Implement arch_irqs_disabled()
  arm64: Implement arch_irqs_disabled()
  nds32: Implement arch_irqs_disabled()
  locking/lockdep: Cleanup
  x86/entry: Remove unused THUNKs
  cpuidle: Move trace_cpu_idle() into generic code
  cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic
  sched,idle,rcu: Push rcu_idle deeper into the idle path
  cpuidle: Fixup IRQ state
  lockdep: Use raw_cpu_*() for per-cpu variables
2020-08-30 11:43:50 -07:00
Peter Zijlstra bf9282dc26 cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic
This allows moving the leave_mm() call into generic code before
rcu_idle_enter(). Gets rid of more trace_*_rcuidle() users.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.369441600@infradead.org
2020-08-26 12:41:53 +02:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Joerg Roedel 7a27ef5e83 x86/mm/64: Update comment in preallocate_vmalloc_pages()
The comment explaining why 4-level systems only need to allocate on
the P4D level caused some confustion. Update it to better explain why
on 4-level systems the allocation on PUD level is necessary.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200814151947.26229-3-joro@8bytes.org
2020-08-15 13:56:16 +02:00
Joerg Roedel 58a18fe95e x86/mm/64: Do not sync vmalloc/ioremap mappings
Remove the code to sync the vmalloc and ioremap ranges for x86-64. The
page-table pages are all pre-allocated so that synchronization is
no longer necessary.

This is a patch that already went into the kernel as:

	commit 8bb9bf242d ("x86/mm/64: Do not sync vmalloc/ioremap mappings")

But it had to be reverted later because it unveiled a bug from:

	commit 6eb82f9940 ("x86/mm: Pre-allocate P4D/PUD pages for vmalloc area")

The bug in that commit causes the P4D/PUD pages not to be correctly
allocated, making the synchronization still necessary. That issue got
fixed meanwhile upstream:

	commit 995909a4e2 ("x86/mm/64: Do not dereference non-present PGD entries")

With that fix it is safe again to remove the page-table synchronization
for vmalloc/ioremap ranges on x86-64.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200814151947.26229-2-joro@8bytes.org
2020-08-15 13:56:16 +02:00
Peter Xu 968614fc7b mm/x86: use general page fault accounting
Use the general page fault accounting by passing regs into
handle_mm_fault().

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20200707225021.200906-23-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:04 -07:00
Peter Xu bce617edec mm: do page fault accounting in handle_mm_fault
Patch series "mm: Page fault accounting cleanups", v5.

This is v5 of the pf accounting cleanup series.  It originates from Gerald
Schaefer's report on an issue a week ago regarding to incorrect page fault
accountings for retried page fault after commit 4064b98270 ("mm: allow
VM_FAULT_RETRY for multiple times"):

  https://lore.kernel.org/lkml/20200610174811.44b94525@thinkpad/

What this series did:

  - Correct page fault accounting: we do accounting for a page fault
    (no matter whether it's from #PF handling, or gup, or anything else)
    only with the one that completed the fault.  For example, page fault
    retries should not be counted in page fault counters.  Same to the
    perf events.

  - Unify definition of PERF_COUNT_SW_PAGE_FAULTS: currently this perf
    event is used in an adhoc way across different archs.

    Case (1): for many archs it's done at the entry of a page fault
    handler, so that it will also cover e.g.  errornous faults.

    Case (2): for some other archs, it is only accounted when the page
    fault is resolved successfully.

    Case (3): there're still quite some archs that have not enabled
    this perf event.

    Since this series will touch merely all the archs, we unify this
    perf event to always follow case (1), which is the one that makes most
    sense.  And since we moved the accounting into handle_mm_fault, the
    other two MAJ/MIN perf events are well taken care of naturally.

  - Unify definition of "major faults": the definition of "major
    fault" is slightly changed when used in accounting (not
    VM_FAULT_MAJOR).  More information in patch 1.

  - Always account the page fault onto the one that triggered the page
    fault.  This does not matter much for #PF handlings, but mostly for
    gup.  More information on this in patch 25.

Patchset layout:

Patch 1:     Introduced the accounting in handle_mm_fault(), not enabled.
Patch 2-23:  Enable the new accounting for arch #PF handlers one by one.
Patch 24:    Enable the new accounting for the rest outliers (gup, iommu, etc.)
Patch 25:    Cleanup GUP task_struct pointer since it's not needed any more

This patch (of 25):

This is a preparation patch to move page fault accountings into the
general code in handle_mm_fault().  This includes both the per task
flt_maj/flt_min counters, and the major/minor page fault perf events.  To
do this, the pt_regs pointer is passed into handle_mm_fault().

PERF_COUNT_SW_PAGE_FAULTS should still be kept in per-arch page fault
handlers.

So far, all the pt_regs pointer that passed into handle_mm_fault() is
NULL, which means this patch should have no intented functional change.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200707225021.200906-1-peterx@redhat.com
Link: http://lkml.kernel.org/r/20200707225021.200906-2-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Jia He d622ecec5f mm/memory_hotplug: introduce default dummy memory_add_physaddr_to_nid()
This is to introduce a general dummy helper.  memory_add_physaddr_to_nid()
is a fallback option to get the nid in case NUMA_NO_NID is detected.

After this patch, arm64/sh/s390 can simply use the general dummy version.
PowerPC/x86/ia64 will still use their specific version.

This is the preparation to set a fallback value for dev_dax->target_node.

Signed-off-by: Jia He <justin.he@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chuhong Yuan <hslester96@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Cc: Kaly Xin <Kaly.Xin@arm.com>
Link: http://lkml.kernel.org/r/20200710031619.18762-2-justin.he@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:57 -07:00
Daniel Jordan fe124c95df x86/mm: use max memory block size on bare metal
Some of our servers spend significant time at kernel boot initializing
memory block sysfs directories and then creating symlinks between them and
the corresponding nodes.  The slowness happens because the machines get
stuck with the smallest supported memory block size on x86 (128M), which
results in 16,288 directories to cover the 2T of installed RAM.  The
search for each memory block is noticeable even with commit 4fb6eabf10
("drivers/base/memory.c: cache memory blocks in xarray to accelerate
lookup").

Commit 078eb6aa50 ("x86/mm/memory_hotplug: determine block size based on
the end of boot memory") chooses the block size based on alignment with
memory end.  That addresses hotplug failures in qemu guests, but for bare
metal systems whose memory end isn't aligned to even the smallest size, it
leaves them at 128M.

Make kernels that aren't running on a hypervisor use the largest supported
size (2G) to minimize overhead on big machines.  Kernel boot goes 7%
faster on the aforementioned servers, shaving off half a second.

[daniel.m.jordan@oracle.com: v3]
  Link: http://lkml.kernel.org/r/20200714205450.945834-1-daniel.m.jordan@oracle.com

Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200609225451.3542648-1-daniel.m.jordan@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:57 -07:00
Linus Torvalds 97d052ea3f A set of locking fixes and updates:
- Untangle the header spaghetti which causes build failures in various
     situations caused by the lockdep additions to seqcount to validate that
     the write side critical sections are non-preemptible.
 
   - The seqcount associated lock debug addons which were blocked by the
     above fallout.
 
     seqcount writers contrary to seqlock writers must be externally
     serialized, which usually happens via locking - except for strict per
     CPU seqcounts. As the lock is not part of the seqcount, lockdep cannot
     validate that the lock is held.
 
     This new debug mechanism adds the concept of associated locks.
     sequence count has now lock type variants and corresponding
     initializers which take a pointer to the associated lock used for
     writer serialization. If lockdep is enabled the pointer is stored and
     write_seqcount_begin() has a lockdep assertion to validate that the
     lock is held.
 
     Aside of the type and the initializer no other code changes are
     required at the seqcount usage sites. The rest of the seqcount API is
     unchanged and determines the type at compile time with the help of
     _Generic which is possible now that the minimal GCC version has been
     moved up.
 
     Adding this lockdep coverage unearthed a handful of seqcount bugs which
     have been addressed already independent of this.
 
     While generaly useful this comes with a Trojan Horse twist: On RT
     kernels the write side critical section can become preemtible if the
     writers are serialized by an associated lock, which leads to the well
     known reader preempts writer livelock. RT prevents this by storing the
     associated lock pointer independent of lockdep in the seqcount and
     changing the reader side to block on the lock when a reader detects
     that a writer is in the write side critical section.
 
  - Conversion of seqcount usage sites to associated types and initializers.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl8xmPYTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoTuQEACyzQCjU8PgehPp9oMqWzaX2fcVyuZO
 QU2yw6gmz2oTz3ZHUNwdW8UnzGh2OWosK3kDruoD9FtSS51lER1/ISfSPCGfyqxC
 KTjOcB1Kvxwq/3LcCx7Zi3ZxWApat74qs3EhYhKtEiQ2Y9xv9rLq8VV1UWAwyxq0
 eHpjlIJ6b6rbt+ARslaB7drnccOsdK+W/roNj4kfyt+gezjBfojGRdMGQNMFcpnv
 shuTC+vYurAVIiVA/0IuizgHfwZiXOtVpjVoEWaxg6bBH6HNuYMYzdSa/YrlDkZs
 n/aBI/Xkvx+Eacu8b1Zwmbzs5EnikUK/2dMqbzXKUZK61eV4hX5c2xrnr1yGWKTs
 F/juh69Squ7X6VZyKVgJ9RIccVueqwR2EprXWgH3+RMice5kjnXH4zURp0GHALxa
 DFPfB6fawcH3Ps87kcRFvjgm6FBo0hJ1AxmsW1dY4ACFB9azFa2euW+AARDzHOy2
 VRsUdhL9CGwtPjXcZ/9Rhej6fZLGBXKr8uq5QiMuvttp4b6+j9FEfBgD4S6h8csl
 AT2c2I9LcbWqyUM9P4S7zY/YgOZw88vHRuDH7tEBdIeoiHfrbSBU7EQ9jlAKq/59
 f+Htu2Io281c005g7DEeuCYvpzSYnJnAitj5Lmp/kzk2Wn3utY1uIAVszqwf95Ul
 81ppn2KlvzUK8g==
 =7Gj+
 -----END PGP SIGNATURE-----

Merge tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Thomas Gleixner:
 "A set of locking fixes and updates:

   - Untangle the header spaghetti which causes build failures in
     various situations caused by the lockdep additions to seqcount to
     validate that the write side critical sections are non-preemptible.

   - The seqcount associated lock debug addons which were blocked by the
     above fallout.

     seqcount writers contrary to seqlock writers must be externally
     serialized, which usually happens via locking - except for strict
     per CPU seqcounts. As the lock is not part of the seqcount, lockdep
     cannot validate that the lock is held.

     This new debug mechanism adds the concept of associated locks.
     sequence count has now lock type variants and corresponding
     initializers which take a pointer to the associated lock used for
     writer serialization. If lockdep is enabled the pointer is stored
     and write_seqcount_begin() has a lockdep assertion to validate that
     the lock is held.

     Aside of the type and the initializer no other code changes are
     required at the seqcount usage sites. The rest of the seqcount API
     is unchanged and determines the type at compile time with the help
     of _Generic which is possible now that the minimal GCC version has
     been moved up.

     Adding this lockdep coverage unearthed a handful of seqcount bugs
     which have been addressed already independent of this.

     While generally useful this comes with a Trojan Horse twist: On RT
     kernels the write side critical section can become preemtible if
     the writers are serialized by an associated lock, which leads to
     the well known reader preempts writer livelock. RT prevents this by
     storing the associated lock pointer independent of lockdep in the
     seqcount and changing the reader side to block on the lock when a
     reader detects that a writer is in the write side critical section.

   - Conversion of seqcount usage sites to associated types and
     initializers"

* tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  locking/seqlock, headers: Untangle the spaghetti monster
  locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header
  x86/headers: Remove APIC headers from <asm/smp.h>
  seqcount: More consistent seqprop names
  seqcount: Compress SEQCNT_LOCKNAME_ZERO()
  seqlock: Fold seqcount_LOCKNAME_init() definition
  seqlock: Fold seqcount_LOCKNAME_t definition
  seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g
  hrtimer: Use sequence counter with associated raw spinlock
  kvm/eventfd: Use sequence counter with associated spinlock
  userfaultfd: Use sequence counter with associated spinlock
  NFSv4: Use sequence counter with associated spinlock
  iocost: Use sequence counter with associated spinlock
  raid5: Use sequence counter with associated spinlock
  vfs: Use sequence counter with associated spinlock
  timekeeping: Use sequence counter with associated raw spinlock
  xfrm: policy: Use sequence counters with associated lock
  netfilter: nft_set_rbtree: Use sequence counter with associated rwlock
  netfilter: conntrack: Use sequence counter with associated spinlock
  sched: tasks: Use sequence counter with associated spinlock
  ...
2020-08-10 19:07:44 -07:00
Linus Torvalds fc80c51fd4 Kbuild updates for v5.9
- run the checker (e.g. sparse) after the compiler
 
  - remove unneeded cc-option tests for old compiler flags
 
  - fix tar-pkg to install dtbs
 
  - introduce ccflags-remove-y and asflags-remove-y syntax
 
  - allow to trace functions in sub-directories of lib/
 
  - introduce hostprogs-always-y and userprogs-always-y syntax
 
  - various Makefile cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl8wJXEVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGMGEP/0jDq/WafbfPN0aU83EqEWLt/sKg
 bluzmf/6HGx3XVRnuAzsHNNqysUx77WJiDsU/jbC/zdH8Iox3Sc1diE2sELLNAfY
 iJmQ8NBPggyU74aYG3OJdpDjz8T9EX/nVaYrjyFlbuXElM+Qvo8Z4Fz6NpWqKWlA
 gU+yGxEPPdX6MLHcSPSIu1hGWx7UT4fgfx3zDFTI2qvbQgQjKtzyTjAH5Cm3o87h
 rfomvHSSoAUg+Fh1LediRh1tJlkdVO+w7c+LNwCswmdBtkZuxecj1bQGUTS8GaLl
 CCWOKYfWp0KsVf1veXNNNaX/ecbp+Y34WErFq3V9Fdq5RmVlp+FPSGMyjDMRiQ/p
 LGvzbJLPpG586MnK8of0dOj6Es6tVPuq6WH2HuvsyTGcZJDpFTTxRcK3HDkE8ig6
 ZtuM3owB/Mep8IzwY2yWQiDrc7TX5Fz8S4hzGPU1zG9cfj4VT6TBqHGAy1Eql/0l
 txj6vJpnbQSdXiIX8MIU3yH35Y7eW3JYWgspTZH5Woj1S/wAWwuG93Fuuxq6mQIJ
 q6LSkMavtOfuCjOA9vJBZewpKXRU6yo0CzWNL/5EZ6z/r/I+DGtfb/qka8oYUDjX
 9H0cecL37AQxDHRPTxCZDQF0TpYiFJ6bmnMftK9NKNuIdvsk9DF7UBa3EdUNIj38
 yKS3rI7Lw55xWuY3
 =bkNQ
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - run the checker (e.g. sparse) after the compiler

 - remove unneeded cc-option tests for old compiler flags

 - fix tar-pkg to install dtbs

 - introduce ccflags-remove-y and asflags-remove-y syntax

 - allow to trace functions in sub-directories of lib/

 - introduce hostprogs-always-y and userprogs-always-y syntax

 - various Makefile cleanups

* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
  kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
  kbuild: introduce hostprogs-always-y and userprogs-always-y
  kbuild: sort hostprogs before passing it to ifneq
  kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
  kbuild: Replace HTTP links with HTTPS ones
  kbuild: trace functions in subdirectories of lib/
  kbuild: introduce ccflags-remove-y and asflags-remove-y
  kbuild: do not export LDFLAGS_vmlinux
  kbuild: always create directories of targets
  powerpc/boot: add DTB to 'targets'
  kbuild: buildtar: add dtbs support
  kbuild: remove cc-option test of -ffreestanding
  kbuild: remove cc-option test of -fno-stack-protector
  Revert "kbuild: Create directory for target DTB"
  kbuild: run the checker after the compiler
2020-08-09 14:10:26 -07:00
Linus Torvalds 81e11336d9 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - a few MM hotfixes

 - kthread, tools, scripts, ntfs and ocfs2

 - some of MM

Subsystems affected by this patch series: kthread, tools, scripts, ntfs,
ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan,
debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore,
sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
  mm: vmscan: consistent update to pgrefill
  mm/vmscan.c: fix typo
  khugepaged: khugepaged_test_exit() check mmget_still_valid()
  khugepaged: retract_page_tables() remember to test exit
  khugepaged: collapse_pte_mapped_thp() protect the pmd lock
  khugepaged: collapse_pte_mapped_thp() flush the right range
  mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible
  mm: thp: replace HTTP links with HTTPS ones
  mm/page_alloc: fix memalloc_nocma_{save/restore} APIs
  mm/page_alloc.c: skip setting nodemask when we are in interrupt
  mm/page_alloc: fallbacks at most has 3 elements
  mm/page_alloc: silence a KASAN false positive
  mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()
  mm/page_alloc.c: simplify pageblock bitmap access
  mm/page_alloc.c: extract the common part in pfn_to_bitidx()
  mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits
  mm/shuffle: remove dynamic reconfiguration
  mm/memory_hotplug: document why shuffle_zone() is relevant
  mm/page_alloc: remove nr_free_pagecache_pages()
  mm: remove vm_total_pages
  ...
2020-08-07 11:39:33 -07:00
Mike Rapoport c89ab04feb mm/sparse: cleanup the code surrounding memory_present()
After removal of CONFIG_HAVE_MEMBLOCK_NODE_MAP we have two equivalent
functions that call memory_present() for each region in memblock.memory:
sparse_memory_present_with_active_regions() and membocks_present().

Moreover, all architectures have a call to either of these functions
preceding the call to sparse_init() and in the most cases they are called
one after the other.

Mark the regions from memblock.memory as present during sparce_init() by
making sparse_init() call memblocks_present(), make memblocks_present()
and memory_present() functions static and remove redundant
sparse_memory_present_with_active_regions() function.

Also remove no longer required HAVE_MEMORY_PRESENT configuration option.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200712083130.22919-1-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:27 -07:00
Anshuman Khandual 56993b4e14 mm/sparsemem: enable vmem_altmap support in vmemmap_alloc_block_buf()
There are many instances where vmemap allocation is often switched between
regular memory and device memory just based on whether altmap is available
or not.  vmemmap_alloc_block_buf() is used in various platforms to
allocate vmemmap mappings.  Lets also enable it to handle altmap based
device memory allocation along with existing regular memory allocations.
This will help in avoiding the altmap based allocation switch in many
places.  To summarize there are two different methods to call
vmemmap_alloc_block_buf().

vmemmap_alloc_block_buf(size, node, NULL)   /* Allocate from system RAM */
vmemmap_alloc_block_buf(size, node, altmap) /* Allocate from altmap */

This converts altmap_alloc_block_buf() into a static function, drops it's
entry from the header and updates Documentation/vm/memory-model.rst.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jia He <justin.he@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yu Zhao <yuzhao@google.com>
Link: http://lkml.kernel.org/r/1594004178-8861-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:27 -07:00
Anshuman Khandual 1d9cfee753 mm/sparsemem: enable vmem_altmap support in vmemmap_populate_basepages()
Patch series "arm64: Enable vmemmap mapping from device memory", v4.

This series enables vmemmap backing memory allocation from device memory
ranges on arm64.  But before that, it enables vmemmap_populate_basepages()
and vmemmap_alloc_block_buf() to accommodate struct vmem_altmap based
alocation requests.

This patch (of 3):

vmemmap_populate_basepages() is used across platforms to allocate backing
memory for vmemmap mapping.  This is used as a standard default choice or
as a fallback when intended huge pages allocation fails.  This just
creates entire vmemmap mapping with base pages (PAGE_SIZE).

On arm64 platforms, vmemmap_populate_basepages() is called instead of the
platform specific vmemmap_populate() when ARM64_SWAPPER_USES_SECTION_MAPS
is not enabled as in case for ARM64_16K_PAGES and ARM64_64K_PAGES configs.

At present vmemmap_populate_basepages() does not support allocating from
driver defined struct vmem_altmap while trying to create vmemmap mapping
for a device memory range.  It prevents ARM64_16K_PAGES and
ARM64_64K_PAGES configs on arm64 from supporting device memory with
vmemap_altmap request.

This enables vmem_altmap support in vmemmap_populate_basepages() unlocking
device memory allocation for vmemap mapping on arm64 platforms with 16K or
64K base page configs.

Each architecture should evaluate and decide on subscribing device memory
based base page allocation through vmemmap_populate_basepages().  Hence
lets keep it disabled on all archs in order to preserve the existing
semantics.  A subsequent patch enables it on arm64.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Jia He <justin.he@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Yu Zhao <yuzhao@google.com>
Link: http://lkml.kernel.org/r/1594004178-8861-1-git-send-email-anshuman.khandual@arm.com
Link: http://lkml.kernel.org/r/1594004178-8861-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:27 -07:00
Mike Rapoport ca15ca406f mm: remove unneeded includes of <asm/pgalloc.h>
Patch series "mm: cleanup usage of <asm/pgalloc.h>"

Most architectures have very similar versions of pXd_alloc_one() and
pXd_free_one() for intermediate levels of page table.  These patches add
generic versions of these functions in <asm-generic/pgalloc.h> and enable
use of the generic functions where appropriate.

In addition, functions declared and defined in <asm/pgalloc.h> headers are
used mostly by core mm and early mm initialization in arch and there is no
actual reason to have the <asm/pgalloc.h> included all over the place.
The first patch in this series removes unneeded includes of
<asm/pgalloc.h>

In the end it didn't work out as neatly as I hoped and moving
pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require
unnecessary changes to arches that have custom page table allocations, so
I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local
to mm/.

This patch (of 8):

In most cases <asm/pgalloc.h> header is required only for allocations of
page table memory.  Most of the .c files that include that header do not
use symbols declared in <asm/pgalloc.h> and do not require that header.

As for the other header files that used to include <asm/pgalloc.h>, it is
possible to move that include into the .c file that actually uses symbols
from <asm/pgalloc.h> and drop the include from the header file.

The process was somewhat automated using

	sed -i -E '/[<"]asm\/pgalloc\.h/d' \
                $(grep -L -w -f /tmp/xx \
                        $(git grep -E -l '[<"]asm/pgalloc\.h'))

where /tmp/xx contains all the symbols defined in
arch/*/include/asm/pgalloc.h.

[rppt@linux.ibm.com: fix powerpc warning]

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:26 -07:00
Joerg Roedel 995909a4e2 x86/mm/64: Do not dereference non-present PGD entries
The code for preallocate_vmalloc_pages() was written under the
assumption that the p4d_offset() and pud_offset() functions will perform
present checks before dereferencing the parent entries.

This assumption is wrong an leads to a bug in the code which causes the
physical address found in the PGD be used as a page-table page, even if
the PGD is not present.

So the code flow currently is:

	pgd = pgd_offset_k(addr);
	p4d = p4d_offset(pgd, addr);
	if (p4d_none(*p4d))
		p4d = p4d_alloc(&init_mm, pgd, addr);

This lacks a check for pgd_none() at least, the correct flow would be:

	pgd = pgd_offset_k(addr);
	if (pgd_none(*pgd))
		p4d = p4d_alloc(&init_mm, pgd, addr);
	else
		p4d = p4d_offset(pgd, addr);

But this is the same flow that the p4d_alloc() and the pud_alloc()
functions use internally, so there is no need to duplicate them.

Remove the p?d_none() checks from the function and just call into
p4d_alloc() and pud_alloc() to correctly pre-allocate the PGD entries.

Reported-and-tested-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Fixes: 6eb82f9940 ("x86/mm: Pre-allocate P4D/PUD pages for vmalloc area")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 09:20:57 -07:00
Linus Torvalds 7b4ea9456d Revert "x86/mm/64: Do not sync vmalloc/ioremap mappings"
This reverts commit 8bb9bf242d.

It seems the vmalloc page tables aren't always preallocated in all
situations, because Jason Donenfeld reports an oops with this commit:

  BUG: unable to handle page fault for address: ffffe8ffffd00608
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] PREEMPT SMP
  CPU: 2 PID: 22 Comm: kworker/2:0 Not tainted 5.8.0+ #154
  RIP: process_one_work+0x2c/0x2d0
  Code: 41 56 41 55 41 54 55 48 89 f5 53 48 89 fb 48 83 ec 08 48 8b 06 4c 8b 67 40 49 89 c6 45 30 f6 a8 04 b8 00 00 00 00 4c 0f 44 f0 <49> 8b 46 08 44 8b a8 00 01 05
  Call Trace:
   worker_thread+0x4b/0x3b0
   ? rescuer_thread+0x360/0x360
   kthread+0x116/0x140
   ? __kthread_create_worker+0x110/0x110
   ret_from_fork+0x1f/0x30
  CR2: ffffe8ffffd00608

and that page fault address is right in that vmalloc space, and we
clearly don't have a PGD/P4D entry for it.

Looking at the "Code:" line, the actual fault seems to come from the
'pwq->wq' dereference at the top of the process_one_work() function:

        struct pool_workqueue *pwq = get_work_pwq(work);
        struct worker_pool *pool = worker->pool;
        bool cpu_intensive = pwq->wq->flags & WQ_CPU_INTENSIVE;

so 'struct pool_workqueue *pwq' is the allocation that hasn't been
synchronized across CPUs.

Just revert for now, while Joerg figures out the cause.

Reported-and-bisected-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-06 12:02:58 -07:00
Peter Zijlstra 0cd39f4600 locking/seqlock, headers: Untangle the spaghetti monster
By using lockdep_assert_*() from seqlock.h, the spaghetti monster
attacked.

Attack back by reducing seqlock.h dependencies from two key high level headers:

 - <linux/seqlock.h>:               -Remove <linux/ww_mutex.h>
 - <linux/time.h>:                  -Remove <linux/seqlock.h>
 - <linux/sched.h>:                 +Add    <linux/seqlock.h>

The price was to add it to sched.h ...

Core header fallout, we add direct header dependencies instead of gaining them
parasitically from higher level headers:

 - <linux/dynamic_queue_limits.h>:  +Add <asm/bug.h>
 - <linux/hrtimer.h>:               +Add <linux/seqlock.h>
 - <linux/ktime.h>:                 +Add <asm/bug.h>
 - <linux/lockdep.h>:               +Add <linux/smp.h>
 - <linux/sched.h>:                 +Add <linux/seqlock.h>
 - <linux/videodev2.h>:             +Add <linux/kernel.h>

Arch headers fallout:

 - PARISC: <asm/timex.h>:           +Add <asm/special_insns.h>
 - SH:     <asm/io.h>:              +Add <asm/page.h>
 - SPARC:  <asm/timer_64.h>:        +Add <uapi/asm/asi.h>
 - SPARC:  <asm/vvar.h>:            +Add <asm/processor.h>, <asm/barrier.h>
                                    -Remove <linux/seqlock.h>
 - X86:    <asm/fixmap.h>:          +Add <asm/pgtable_types.h>
                                    -Remove <asm/acpi.h>

There's also a bunch of parasitic header dependency fallout in .c files, not listed
separately.

[ mingo: Extended the changelog, split up & fixed the original patch. ]

Co-developed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200804133438.GK2674@hirez.programming.kicks-ass.net
2020-08-06 16:13:13 +02:00
Linus Torvalds 125cfa0d4d The conversion of X86 syscall, interrupt and exception entry/exit handling
to the generic code. Pretty much a straight forward 1:1 conversion plus the
 consolidation of the KVM handling of pending work before entering guest
 mode.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl8pEFgTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYocEwD/474Eb7LzZ8yahyUBirWJP3k3qzgs9j
 dZUxqB6LNuDOstEyTGLPdx1dmQP2vHbFfjoM7YBOH37EGcHsqjGliLvn2Y05ZD7O
 6kYwjz6qVnJcm3IMtfSUn/8LkfO5pGUdKd3U5ngDmPLpkeaQ4nPKqiO0uIb0wzwa
 cO7l10tG4YjMCWQxPNIaOh8kncLieQBediJPFjkQjV+Fh33kSU3LWTl3fccz6b5+
 mgSUFL0qjQpp+Nl7lCaDQQiAop9GTUETfDtximRydZauiM2NpCfz+QBmQzq50Xv1
 G3DWZoBIZBjmWJUgfSmS/s4GOYkBTBnT/fUcZmIDcgdRwvtEvRzIhcP87/wn7P3N
 UKpLdHqmvA0BFDXZbNZgS362++29pj5Lnb+u3QbWSKQ9UqHN0NUlSY4wzfTLXsGp
 Mzpp4TW0u/8kyOlo7wK3lVDgNJaPG31aiNVuDPgLe4cEluO5cq7/7g2GcFBqF1Ly
 SqNGD1IccteNQTNvDopczPy7qUl5Lal+Ia06szNSPR48gLrvhSWdyYr2i1sD7vx4
 hAhR0Hsi9dacGv46TrRw1OdDzq9bOW68G8GIgLJgDXaayPXLnx6TQEUjzQtIkE/i
 ydTPUarp5QOFByt+RBjI90ZcW4RuLgMTOEVONPXtSn8IoCP2Kdg9u3gD9AmUW3Q2
 JFkKMiSiJPGxlw==
 =84y7
 -----END PGP SIGNATURE-----

Merge tag 'x86-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 conversion to generic entry code from Thomas Gleixner:
 "The conversion of X86 syscall, interrupt and exception entry/exit
  handling to the generic code.

  Pretty much a straight-forward 1:1 conversion plus the consolidation
  of the KVM handling of pending work before entering guest mode"

* tag 'x86-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kvm: Use __xfer_to_guest_mode_work_pending() in kvm_run_vcpu()
  x86/kvm: Use generic xfer to guest work function
  x86/entry: Cleanup idtentry_enter/exit
  x86/entry: Use generic interrupt entry/exit code
  x86/entry: Cleanup idtentry_entry/exit_user
  x86/entry: Use generic syscall exit functionality
  x86/entry: Use generic syscall entry function
  x86/ptrace: Provide pt_regs helper for entry/exit
  x86/entry: Move user return notifier out of loop
  x86/entry: Consolidate 32/64 bit syscall entry
  x86/entry: Consolidate check_user_regs()
  x86: Correct noinstr qualifiers
  x86/idtentry: Remove stale comment
2020-08-04 21:05:46 -07:00
Linus Torvalds 99ea1521a0 Remove uninitialized_var() macro for v5.9-rc1
- Clean up non-trivial uses of uninitialized_var()
 - Update documentation and checkpatch for uninitialized_var() removal
 - Treewide removal of uninitialized_var()
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAl8oYLQWHGtlZXNjb29r
 QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJsfjEACvf0D3WL3H7sLHtZ2HeMwOgAzq
 il08t6vUscINQwiIIK3Be43ok3uQ1Q+bj8sr2gSYTwunV2IYHFferzgzhyMMno3o
 XBIGd1E+v1E4DGBOiRXJvacBivKrfvrdZ7AWiGlVBKfg2E0fL1aQbe9AYJ6eJSbp
 UGqkBkE207dugS5SQcwrlk1tWKUL089lhDAPd7iy/5RK76OsLRCJFzIerLHF2ZK2
 BwvA+NWXVQI6pNZ0aRtEtbbxwEU4X+2J/uaXH5kJDszMwRrgBT2qoedVu5LXFPi8
 +B84IzM2lii1HAFbrFlRyL/EMueVFzieN40EOB6O8wt60Y4iCy5wOUzAdZwFuSTI
 h0xT3JI8BWtpB3W+ryas9cl9GoOHHtPA8dShuV+Y+Q2bWe1Fs6kTl2Z4m4zKq56z
 63wQCdveFOkqiCLZb8s6FhnS11wKtAX4czvXRXaUPgdVQS1Ibyba851CRHIEY+9I
 AbtogoPN8FXzLsJn7pIxHR4ADz+eZ0dQ18f2hhQpP6/co65bYizNP5H3h+t9hGHG
 k3r2k8T+jpFPaddpZMvRvIVD8O2HvJZQTyY6Vvneuv6pnQWtr2DqPFn2YooRnzoa
 dbBMtpon+vYz6OWokC5QNWLqHWqvY9TmMfcVFUXE4AFse8vh4wJ8jJCNOFVp8On+
 drhmmImUr1YylrtVOw==
 =xHmk
 -----END PGP SIGNATURE-----

Merge tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull uninitialized_var() macro removal from Kees Cook:
 "This is long overdue, and has hidden too many bugs over the years. The
  series has several "by hand" fixes, and then a trivial treewide
  replacement.

   - Clean up non-trivial uses of uninitialized_var()

   - Update documentation and checkpatch for uninitialized_var() removal

   - Treewide removal of uninitialized_var()"

* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  compiler: Remove uninitialized_var() macro
  treewide: Remove uninitialized_var() usage
  checkpatch: Remove awareness of uninitialized_var() macro
  mm/debug_vm_pgtable: Remove uninitialized_var() usage
  f2fs: Eliminate usage of uninitialized_var() macro
  media: sur40: Remove uninitialized_var() usage
  KVM: PPC: Book3S PR: Remove uninitialized_var() usage
  clk: spear: Remove uninitialized_var() usage
  clk: st: Remove uninitialized_var() usage
  spi: davinci: Remove uninitialized_var() usage
  ide: Remove uninitialized_var() usage
  rtlwifi: rtl8192cu: Remove uninitialized_var() usage
  b43: Remove uninitialized_var() usage
  drbd: Remove uninitialized_var() usage
  x86/mm/numa: Remove uninitialized_var() usage
  docs: deprecated.rst: Add uninitialized_var()
2020-08-04 13:49:43 -07:00
Linus Torvalds e96ec8cf9c The biggest change is to not sync the vmalloc and ioremap ranges for x86-64 anymore.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl8oW+oRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1hEsBAAkFaP2QXd8Nc3nqA+eQoBwSty5NumQWNi
 /VC4nt2R3vqa547XgMgT0RslrftUeCZ6bI0gs7yG6vCrjHbsiFzqliOUPJPXHoUE
 MQMw0tw1x7ODVsAGkzJ5YYrhBvZ2rDvaewAHNRLdkmdLJwXobpCHk4YM48O0oInh
 rlTC9Lgu4jOGOUBazZt4a1xAZGbMK4uk6Er14HGONoqwHV0XC4lDnJm7qNWJLquE
 KEFPWyEC6/T4Vwtmc98eDd+/gJ3sDC2tRtRalW0U5BZQXWjbMLUh/g5aJF8g0NG1
 kmHgbIf5todhFgl/D7ZWJ/i6jucGSZ1u43IsOQwuQ2U/flsUrHDPxbLW55r1axld
 K/RdvWvanWBb1A77Z/2h9eMwm0saEBjQT/UmtT4fNQpgUHJ1AJaVLHcgeFWQsVVX
 AbrP6DAGkEV7QqxQjCl9PK4kOi6BNwvKIfKmFsy5+Ypgx9e39OZmd9FMNt7mJslC
 2htTdXsUYUgwCrQH9brUjUs943mrvWXUYdencvVw1ByWwkSTRm5owXL0w3XtKuwN
 fEtcq0Y6ALeTwjyN0sja3johR93qaHWmyI8t5NLzT+g1rQgrd9Hae6dChyx1nzlz
 I5xIQF4ropZhhP6vcifiyDQcltOZsspVOMQzLTepuqZEpqDEoUtbjZhI4JcS51nc
 qe5rEOGGa00=
 =D9UW
 -----END PGP SIGNATURE-----

Merge tag 'x86-mm-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mmm update from Ingo Molnar:
 "The biggest change is to not sync the vmalloc and ioremap ranges for
  x86-64 anymore"

* tag 'x86-mm-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/64: Make sync_global_pgds() static
  x86/mm/64: Do not sync vmalloc/ioremap mappings
  x86/mm: Pre-allocate P4D/PUD pages for vmalloc area
2020-08-03 17:25:42 -07:00
Linus Torvalds 37e88224c0 Misc cleanups all around the place.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl8oRTgRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1huHQ//T2hZk5zlpOtojxvdAzsPgtV4tHawseK8
 +ZZEbrH5qo5/ZMF18qyEJCm9p1yg8uIu71InULRCSgjU3v82GVCcuLXuE36U904G
 gHUqkYPnqxCqx+Li125aye9tKWahXe1DxX+uWbV0Ju7fiCO0rwYIzpWn1bnR6ilp
 fmLGSbgPlTVJwZ9mBvyi3VUlH5tDYidFN74TREUOwx2g5uhg+8uEo44Eb/bx8ESF
 dGt1Z/fnfDHkUZtmhzJk5Uz8nbw7rPHU/EZ4iZAxEzxTutY5PhsvbIfLO4t4HhGn
 utZCk/pIdiLLQ1GaTvFxqi3iolDqpOuXpnDlfEAJD8UlMCnwyh1Certq5LaRbtHS
 8SW3/CeJgzqzrrsYhkxVu2PMFWriSMxgKTLiN0KnzJN0Hu7A5lHbBY/6G7zpsF/A
 2KJ4e8lZiPCcNF7LteSRroUe4hNOYxZ2FlYTXm3AgycSL189UMfWlHFb5c+b4m1a
 cNJpz+jAom8foXN4KhRkl5PFKXVXDGTVln3NRJCh1Mqd1Ef4hsTo9H6FgHX/EfHg
 slJDwwPac80v0dzlMTSsMkyseaKRAqIObWOiknPt1wv/qja7ibVZ5mUbZ+/mfJX/
 YWybcPi1omgUSNt7TNx6jtma67rUjmJW0x9g7UJ/ttEkf6yG2lemrdusydBYuIni
 0Z2+hWzI9MM=
 =X7o0
 -----END PGP SIGNATURE-----

Merge tag 'x86-cleanups-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups all around the place"

* tag 'x86-cleanups-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ioperm: Initialize pointer bitmap with NULL rather than 0
  x86: uv: uv_hub.h: Delete duplicated word
  x86: cmpxchg_32.h: Delete duplicated word
  x86: bootparam.h: Delete duplicated word
  x86/mm: Remove the unused mk_kernel_pgd() #define
  x86/tsc: Remove unused "US_SCALE" and "NS_SCALE" leftover macros
  x86/ioapic: Remove unused "IOAPIC_AUTO" define
  x86/mm: Drop unused MAX_PHYSADDR_BITS
  x86/msr: Move the F15h MSRs where they belong
  x86/idt: Make idt_descr static
  initrd: Remove erroneous comment
  x86/mm/32: Fix -Wmissing prototypes warnings for init.c
  cpu/speculation: Add prototype for cpu_show_srbds()
  x86/mm: Fix -Wmissing-prototypes warnings for arch/x86/mm/init.c
  x86/asm: Unify __ASSEMBLY__ blocks
  x86/cpufeatures: Mark two free bits in word 3
  x86/msr: Lift AMD family 0x15 power-specific MSRs
2020-08-03 16:53:28 -07:00
Ingo Molnar 63722bbca6 Merge branch 'kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core
Pull v5.9 KCSAN bits from Paul E. McKenney.

Perhaps the most important change is that GCC 11 now has all fixes in place
to support KCSAN, so GCC support can be enabled again.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-08-01 09:26:27 +02:00
Joerg Roedel 2b32ab031e x86/mm/64: Make sync_global_pgds() static
The function is only called from within init_64.c and can be static.
Also remove it from pgtable_64.h.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/20200721095953.6218-4-joro@8bytes.org
2020-07-27 12:32:29 +02:00
Joerg Roedel 8bb9bf242d x86/mm/64: Do not sync vmalloc/ioremap mappings
Remove the code to sync the vmalloc and ioremap ranges for x86-64. The
page-table pages are all pre-allocated now so that synchronization is
no longer necessary.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/20200721095953.6218-3-joro@8bytes.org
2020-07-27 12:32:29 +02:00
Joerg Roedel 6eb82f9940 x86/mm: Pre-allocate P4D/PUD pages for vmalloc area
Pre-allocate the page-table pages for the vmalloc area at the level
which needs synchronization on x86-64, which is P4D for 5-level and
PUD for 4-level paging.

Doing this at boot makes sure no synchronization of that area is
necessary at runtime. The synchronization takes the pgd_lock and
iterates over all page-tables in the system, so it can take quite long
and is better avoided.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/20200721095953.6218-2-joro@8bytes.org
2020-07-27 12:32:29 +02:00
Ingo Molnar 2d65685a4a Merge branch 'x86/urgent' into x86/cleanups
Refresh the branch for a dependent commit.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-07-26 19:52:30 +02:00
Thomas Gleixner a27a0a5549 x86/entry: Cleanup idtentry_enter/exit
Remove the temporary defines and fixup all references.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200722220520.855839271@linutronix.de
2020-07-24 15:05:01 +02:00
Kees Cook aecfd220b2 x86/mm/numa: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings (e.g.
"unused variable"). If the compiler thinks it is uninitialized, either
simply initialize the variable or make compiler changes. As a precursor
to removing[2] this[3] macro[4], refactor code to avoid its need.

The original reason for its use here was to work around the #ifdef
being the only place the variable was used. This is better expressed
using IS_ENABLED() and a new code block where the variable can be used
unconditionally.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Fixes: 1e01979c8f ("x86, numa: Implement pfn -> nid mapping granularity check")
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:32:25 -07:00
Masahiro Yamada 893ab00439 kbuild: remove cc-option test of -fno-stack-protector
Some Makefiles already pass -fno-stack-protector unconditionally.
For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.

No problem report so far about hard-coding this option. So, we can
assume all supported compilers know -fno-stack-protector.

GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN)

Get rid of cc-option from -fno-stack-protector.

Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'.

Note:
arch/mips/vdso/Makefile adds -fno-stack-protector twice, first
unconditionally, and second conditionally. I removed the second one.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-07-07 11:13:10 +09:00
Andy Lutomirski b037b09b90 x86/entry: Rename idtentry_enter/exit_cond_rcu() to idtentry_enter/exit()
They were originally called _cond_rcu because they were special versions
with conditional RCU handling.  Now they're the standard entry and exit
path, so the _cond_rcu part is just confusing.  Drop it.

Also change the signature to make them more extensible and more foolproof.

No functional change -- it's pure refactoring.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/247fc67685263e0b673e1d7f808182d28ff80359.1593795633.git.luto@kernel.org
2020-07-06 21:15:52 +02:00
Qian Cai cb38f82043 x86/mm/pat: Mark an intentional data race
cpa_4k_install could be accessed concurrently as noticed by KCSAN,

read to 0xffffffffaa59a000 of 8 bytes by interrupt on cpu 7:
cpa_inc_4k_install arch/x86/mm/pat/set_memory.c:131 [inline]
__change_page_attr+0x10cf/0x1840 arch/x86/mm/pat/set_memory.c:1514
__change_page_attr_set_clr+0xce/0x490 arch/x86/mm/pat/set_memory.c:1636
__set_pages_np+0xc4/0xf0 arch/x86/mm/pat/set_memory.c:2148
__kernel_map_pages+0xb0/0xc8 arch/x86/mm/pat/set_memory.c:2178
kernel_map_pages include/linux/mm.h:2719 [inline] <snip>

write to 0xffffffffaa59a000 of 8 bytes by task 1 on cpu 6:
cpa_inc_4k_install arch/x86/mm/pat/set_memory.c:131 [inline]
__change_page_attr+0x10ea/0x1840 arch/x86/mm/pat/set_memory.c:1514
__change_page_attr_set_clr+0xce/0x490 arch/x86/mm/pat/set_memory.c:1636
__set_pages_p+0xc4/0xf0 arch/x86/mm/pat/set_memory.c:2129
__kernel_map_pages+0x2e/0xc8 arch/x86/mm/pat/set_memory.c:2176
kernel_map_pages include/linux/mm.h:2719 [inline] <snip>

Both accesses are due to the same "cpa_4k_install++" in
cpa_inc_4k_install. A data race here could be potentially undesirable:
depending on compiler optimizations or how x86 executes a non-LOCK'd
increment, it may lose increments, corrupt the counter, etc. Since this
counter only seems to be used for printing some stats, this data race
itself is unlikely to cause harm to the system though. Thus, mark this
intentional data race using the data_race() marco.

Suggested-by: Macro Elver <elver@google.com>
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29 12:04:47 -07:00
Christoph Hellwig 25f12ae45f maccess: rename probe_kernel_address to get_kernel_nofault
Better describe what this helper does, and match the naming of
copy_from_kernel_nofault.

Also switch the argument order around, so that it acts and looks
like get_user().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-18 11:14:40 -07:00
Christoph Hellwig fe557319aa maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17 10:57:41 -07:00
Benjamin Thiel d5249bc7a1 x86/mm: Fix -Wmissing-prototypes warnings for arch/x86/mm/init.c
Fix -Wmissing-prototypes warnings:

  arch/x86/mm/init.c:81:6:
  warning: no previous prototype for ‘x86_has_pat_wp’ [-Wmissing-prototypes]
  bool x86_has_pat_wp(void)

  arch/x86/mm/init.c:86:22:
  warning: no previous prototype for ‘pgprot2cachemode’ [-Wmissing-prototypes]
  enum page_cache_mode pgprot2cachemode(pgprot_t pgprot)

by including the respective header containing prototypes. Also fix:

  arch/x86/mm/init.c:893:13:
  warning: no previous prototype for ‘mem_encrypt_free_decrypted_mem’ [-Wmissing-prototypes]
  void __weak mem_encrypt_free_decrypted_mem(void) { }

by making it static inline for the !CONFIG_AMD_MEM_ENCRYPT case. This
warning happens when CONFIG_AMD_MEM_ENCRYPT is not enabled (defconfig
for example):

  ./arch/x86/include/asm/mem_encrypt.h:80:27:
  warning: inline function ‘mem_encrypt_free_decrypted_mem’ declared weak [-Wattributes]
  static inline void __weak mem_encrypt_free_decrypted_mem(void) { }
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

It's ok to convert to static inline because the function is used only in
x86. Is not shared with other architectures so drop the __weak too.

 [ bp: Massage and adjust __weak comments while at it. ]

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200606122629.2720-1-b.thiel@posteo.de
2020-06-17 10:45:46 +02:00
Linus Torvalds 076f14be7f The X86 entry, exception and interrupt code rework
This all started about 6 month ago with the attempt to move the Posix CPU
 timer heavy lifting out of the timer interrupt code and just have lockless
 quick checks in that code path. Trivial 5 patches.
 
 This unearthed an inconsistency in the KVM handling of task work and the
 review requested to move all of this into generic code so other
 architectures can share.
 
 Valid request and solved with another 25 patches but those unearthed
 inconsistencies vs. RCU and instrumentation.
 
 Digging into this made it obvious that there are quite some inconsistencies
 vs. instrumentation in general. The int3 text poke handling in particular
 was completely unprotected and with the batched update of trace events even
 more likely to expose to endless int3 recursion.
 
 In parallel the RCU implications of instrumenting fragile entry code came
 up in several discussions.
 
 The conclusion of the X86 maintainer team was to go all the way and make
 the protection against any form of instrumentation of fragile and dangerous
 code pathes enforcable and verifiable by tooling.
 
 A first batch of preparatory work hit mainline with commit d5f744f9a2.
 
 The (almost) full solution introduced a new code section '.noinstr.text'
 into which all code which needs to be protected from instrumentation of all
 sorts goes into. Any call into instrumentable code out of this section has
 to be annotated. objtool has support to validate this. Kprobes now excludes
 this section fully which also prevents BPF from fiddling with it and all
 'noinstr' annotated functions also keep ftrace off. The section, kprobes
 and objtool changes are already merged.
 
 The major changes coming with this are:
 
     - Preparatory cleanups
 
     - Annotating of relevant functions to move them into the noinstr.text
       section or enforcing inlining by marking them __always_inline so the
       compiler cannot misplace or instrument them.
 
     - Splitting and simplifying the idtentry macro maze so that it is now
       clearly separated into simple exception entries and the more
       interesting ones which use interrupt stacks and have the paranoid
       handling vs. CR3 and GS.
 
     - Move quite some of the low level ASM functionality into C code:
 
        - enter_from and exit to user space handling. The ASM code now calls
          into C after doing the really necessary ASM handling and the return
 	 path goes back out without bells and whistels in ASM.
 
        - exception entry/exit got the equivivalent treatment
 
        - move all IRQ tracepoints from ASM to C so they can be placed as
          appropriate which is especially important for the int3 recursion
          issue.
 
     - Consolidate the declaration and definition of entry points between 32
       and 64 bit. They share a common header and macros now.
 
     - Remove the extra device interrupt entry maze and just use the regular
       exception entry code.
 
     - All ASM entry points except NMI are now generated from the shared header
       file and the corresponding macros in the 32 and 64 bit entry ASM.
 
     - The C code entry points are consolidated as well with the help of
       DEFINE_IDTENTRY*() macros. This allows to ensure at one central point
       that all corresponding entry points share the same semantics. The
       actual function body for most entry points is in an instrumentable
       and sane state.
 
       There are special macros for the more sensitive entry points,
       e.g. INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
       They allow to put the whole entry instrumentation and RCU handling
       into safe places instead of the previous pray that it is correct
       approach.
 
     - The INT3 text poke handling is now completely isolated and the
       recursion issue banned. Aside of the entry rework this required other
       isolation work, e.g. the ability to force inline bsearch.
 
     - Prevent #DB on fragile entry code, entry relevant memory and disable
       it on NMI, #MC entry, which allowed to get rid of the nested #DB IST
       stack shifting hackery.
 
     - A few other cleanups and enhancements which have been made possible
       through this and already merged changes, e.g. consolidating and
       further restricting the IDT code so the IDT table becomes RO after
       init which removes yet another popular attack vector
 
     - About 680 lines of ASM maze are gone.
 
 There are a few open issues:
 
    - An escape out of the noinstr section in the MCE handler which needs
      some more thought but under the aspect that MCE is a complete
      trainwreck by design and the propability to survive it is low, this was
      not high on the priority list.
 
    - Paravirtualization
 
      When PV is enabled then objtool complains about a bunch of indirect
      calls out of the noinstr section. There are a few straight forward
      ways to fix this, but the other issues vs. general correctness were
      more pressing than parawitz.
 
    - KVM
 
      KVM is inconsistent as well. Patches have been posted, but they have
      not yet been commented on or picked up by the KVM folks.
 
    - IDLE
 
      Pretty much the same problems can be found in the low level idle code
      especially the parts where RCU stopped watching. This was beyond the
      scope of the more obvious and exposable problems and is on the todo
      list.
 
 The lesson learned from this brain melting exercise to morph the evolved
 code base into something which can be validated and understood is that once
 again the violation of the most important engineering principle
 "correctness first" has caused quite a few people to spend valuable time on
 problems which could have been avoided in the first place. The "features
 first" tinkering mindset really has to stop.
 
 With that I want to say thanks to everyone involved in contributing to this
 effort. Special thanks go to the following people (alphabetical order):
 
    Alexandre Chartre
    Andy Lutomirski
    Borislav Petkov
    Brian Gerst
    Frederic Weisbecker
    Josh Poimboeuf
    Juergen Gross
    Lai Jiangshan
    Macro Elver
    Paolo Bonzini
    Paul McKenney
    Peter Zijlstra
    Vitaly Kuznetsov
    Will Deacon
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl7j510THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoU2WD/4refvaNm08fG7aiVYem3JJzr0+Pq5O
 /opwnI/1D973ApApj5W/Nd53sN5tVqOiXncSKgywRBWZxRCAGjVYypl9rjpvXu4l
 HlMjhEKBmWkDryxxrM98Vr7hl3hnId5laR56oFfH+G4LUsItaV6Uak/HfXZ4Mq1k
 iYVbEtl2CN+KJjvSgZ6Y1l853Ab5mmGvmeGNHHWCj8ZyjF3cOLoelDTQNnsb0wXM
 crKXBcXJSsCWKYyJ5PTvB82crQCET7Su+LgwK06w/ZbW1//2hVIjSCiN5o/V+aRJ
 06BZNMj8v9tfglkN8LEQvRIjTlnEQ2sq3GxbrVtA53zxkzbBCBJQ96w8yYzQX0ux
 yhqQ/aIZJ1wTYEjJzSkftwLNMRHpaOUnKvJndXRKAYi+eGI7syF61qcZSYGKuAQ/
 bK3b/CzU6QWr1235oTADxh4isEwxA0Pg5wtJCfDDOG0MJ9ALMSOGUkhoiz5EqpkU
 mzFAwfG/Uj7hRjlkms7Yj2OjZfnU7iypj63GgpXghLjr5ksRFKEOMw8e1GXltVHs
 zzwghUjqp2EPq0VOOQn3lp9lol5Prc3xfFHczKpO+CJW6Rpa4YVdqJmejBqJy/on
 Hh/T/ST3wa2qBeAw89vZIeWiUJZZCsQ0f//+2hAbzJY45Y6DuR9vbTAPb9agRgOM
 xg+YaCfpQqFc1A==
 =llba
 -----END PGP SIGNATURE-----

Merge tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry updates from Thomas Gleixner:
 "The x86 entry, exception and interrupt code rework

  This all started about 6 month ago with the attempt to move the Posix
  CPU timer heavy lifting out of the timer interrupt code and just have
  lockless quick checks in that code path. Trivial 5 patches.

  This unearthed an inconsistency in the KVM handling of task work and
  the review requested to move all of this into generic code so other
  architectures can share.

  Valid request and solved with another 25 patches but those unearthed
  inconsistencies vs. RCU and instrumentation.

  Digging into this made it obvious that there are quite some
  inconsistencies vs. instrumentation in general. The int3 text poke
  handling in particular was completely unprotected and with the batched
  update of trace events even more likely to expose to endless int3
  recursion.

  In parallel the RCU implications of instrumenting fragile entry code
  came up in several discussions.

  The conclusion of the x86 maintainer team was to go all the way and
  make the protection against any form of instrumentation of fragile and
  dangerous code pathes enforcable and verifiable by tooling.

  A first batch of preparatory work hit mainline with commit
  d5f744f9a2 ("Pull x86 entry code updates from Thomas Gleixner")

  That (almost) full solution introduced a new code section
  '.noinstr.text' into which all code which needs to be protected from
  instrumentation of all sorts goes into. Any call into instrumentable
  code out of this section has to be annotated. objtool has support to
  validate this.

  Kprobes now excludes this section fully which also prevents BPF from
  fiddling with it and all 'noinstr' annotated functions also keep
  ftrace off. The section, kprobes and objtool changes are already
  merged.

  The major changes coming with this are:

    - Preparatory cleanups

    - Annotating of relevant functions to move them into the
      noinstr.text section or enforcing inlining by marking them
      __always_inline so the compiler cannot misplace or instrument
      them.

    - Splitting and simplifying the idtentry macro maze so that it is
      now clearly separated into simple exception entries and the more
      interesting ones which use interrupt stacks and have the paranoid
      handling vs. CR3 and GS.

    - Move quite some of the low level ASM functionality into C code:

       - enter_from and exit to user space handling. The ASM code now
         calls into C after doing the really necessary ASM handling and
         the return path goes back out without bells and whistels in
         ASM.

       - exception entry/exit got the equivivalent treatment

       - move all IRQ tracepoints from ASM to C so they can be placed as
         appropriate which is especially important for the int3
         recursion issue.

    - Consolidate the declaration and definition of entry points between
      32 and 64 bit. They share a common header and macros now.

    - Remove the extra device interrupt entry maze and just use the
      regular exception entry code.

    - All ASM entry points except NMI are now generated from the shared
      header file and the corresponding macros in the 32 and 64 bit
      entry ASM.

    - The C code entry points are consolidated as well with the help of
      DEFINE_IDTENTRY*() macros. This allows to ensure at one central
      point that all corresponding entry points share the same
      semantics. The actual function body for most entry points is in an
      instrumentable and sane state.

      There are special macros for the more sensitive entry points, e.g.
      INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
      They allow to put the whole entry instrumentation and RCU handling
      into safe places instead of the previous pray that it is correct
      approach.

    - The INT3 text poke handling is now completely isolated and the
      recursion issue banned. Aside of the entry rework this required
      other isolation work, e.g. the ability to force inline bsearch.

    - Prevent #DB on fragile entry code, entry relevant memory and
      disable it on NMI, #MC entry, which allowed to get rid of the
      nested #DB IST stack shifting hackery.

    - A few other cleanups and enhancements which have been made
      possible through this and already merged changes, e.g.
      consolidating and further restricting the IDT code so the IDT
      table becomes RO after init which removes yet another popular
      attack vector

    - About 680 lines of ASM maze are gone.

  There are a few open issues:

   - An escape out of the noinstr section in the MCE handler which needs
     some more thought but under the aspect that MCE is a complete
     trainwreck by design and the propability to survive it is low, this
     was not high on the priority list.

   - Paravirtualization

     When PV is enabled then objtool complains about a bunch of indirect
     calls out of the noinstr section. There are a few straight forward
     ways to fix this, but the other issues vs. general correctness were
     more pressing than parawitz.

   - KVM

     KVM is inconsistent as well. Patches have been posted, but they
     have not yet been commented on or picked up by the KVM folks.

   - IDLE

     Pretty much the same problems can be found in the low level idle
     code especially the parts where RCU stopped watching. This was
     beyond the scope of the more obvious and exposable problems and is
     on the todo list.

  The lesson learned from this brain melting exercise to morph the
  evolved code base into something which can be validated and understood
  is that once again the violation of the most important engineering
  principle "correctness first" has caused quite a few people to spend
  valuable time on problems which could have been avoided in the first
  place. The "features first" tinkering mindset really has to stop.

  With that I want to say thanks to everyone involved in contributing to
  this effort. Special thanks go to the following people (alphabetical
  order): Alexandre Chartre, Andy Lutomirski, Borislav Petkov, Brian
  Gerst, Frederic Weisbecker, Josh Poimboeuf, Juergen Gross, Lai
  Jiangshan, Macro Elver, Paolo Bonzin,i Paul McKenney, Peter Zijlstra,
  Vitaly Kuznetsov, and Will Deacon"

* tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (142 commits)
  x86/entry: Force rcu_irq_enter() when in idle task
  x86/entry: Make NMI use IDTENTRY_RAW
  x86/entry: Treat BUG/WARN as NMI-like entries
  x86/entry: Unbreak __irqentry_text_start/end magic
  x86/entry: __always_inline CR2 for noinstr
  lockdep: __always_inline more for noinstr
  x86/entry: Re-order #DB handler to avoid *SAN instrumentation
  x86/entry: __always_inline arch_atomic_* for noinstr
  x86/entry: __always_inline irqflags for noinstr
  x86/entry: __always_inline debugreg for noinstr
  x86/idt: Consolidate idt functionality
  x86/idt: Cleanup trap_init()
  x86/idt: Use proper constants for table size
  x86/idt: Add comments about early #PF handling
  x86/idt: Mark init only functions __init
  x86/entry: Rename trace_hardirqs_off_prepare()
  x86/entry: Clarify irq_{enter,exit}_rcu()
  x86/entry: Remove DBn stacks
  x86/entry: Remove debug IDT frobbing
  x86/entry: Optimize local_db_save() for virt
  ...
2020-06-13 10:05:47 -07:00
Andy Lutomirski 15a416e8aa x86/entry: Treat BUG/WARN as NMI-like entries
BUG/WARN are cleverly optimized using UD2 to handle the BUG/WARN out of
line in an exception fixup.

But if BUG or WARN is issued in a funny RCU context, then the
idtentry_enter...() path might helpfully WARN that the RCU context is
invalid, which results in infinite recursion.

Split the BUG/WARN handling into an nmi_enter()/nmi_exit() path in
exc_invalid_op() to increase the chance to survive the experience.

[ tglx: Make the declaration match the implementation ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/f8fe40e0088749734b4435b554f73eee53dcf7a8.1591932307.git.luto@kernel.org
2020-06-12 12:12:57 +02:00
Thomas Gleixner 37d1a04b13 Rebase locking/kcsan to locking/urgent
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.

Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11 20:02:46 +02:00
Thomas Gleixner f0178fc01f x86/entry: Unbreak __irqentry_text_start/end magic
The entry rework moved interrupt entry code from the irqentry to the
noinstr section which made the irqentry section empty.

This breaks boundary checks which rely on the __irqentry_text_start/end
markers to find out whether a function in a stack trace is
interrupt/exception entry code. This affects the function graph tracer and
filter_irq_stacks().

As the IDT entry points are all sequentialy emitted this is rather simple
to unbreak by injecting __irqentry_text_start/end as global labels.

To make this work correctly:

  - Remove the IRQENTRY_TEXT section from the x86 linker script
  - Define __irqentry so it breaks the build if it's used
  - Adjust the entry mirroring in PTI
  - Remove the redundant kprobes and unwinder bound checks

Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11 15:15:29 +02:00
Thomas Gleixner 3e77abda65 x86/idt: Consolidate idt functionality
- Move load_current_idt() out of line and replace the hideous comment with
   a lockdep assert. This allows to make idt_table and idt_descr static.

 - Mark idt_table read only after the IDT initialization is complete.

 - Shuffle code around to consolidate the #ifdef sections into one.

 - Adapt the F00F bug code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200528145523.084915381@linutronix.de
2020-06-11 15:15:26 +02:00
Peter Zijlstra fd501d4f03 x86/entry: Remove DBn stacks
Both #DB itself, as all other IST users (NMI, #MC) now clear DR7 on
entry. Combined with not allowing breakpoints on entry/noinstr/NOKPROBE
text and no single step (EFLAGS.TF) inside the #DB handler should guarantee
no nested #DB.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.303027161@infradead.org
2020-06-11 15:15:23 +02:00
Thomas Gleixner 91eeafea1e x86/entry: Switch page fault exception to IDTENTRY_RAW
Convert page fault exceptions to IDTENTRY_RAW:

  - Implement the C entry point with DEFINE_IDTENTRY_RAW
  - Add the CR2 read into the exception handler
  - Add the idtentry_enter/exit_cond_rcu() invocations in
    in the regular page fault handler and in the async PF
    part.
  - Emit the ASM stub with DECLARE_IDTENTRY_RAW
  - Remove the ASM idtentry in 64-bit
  - Remove the CR2 read from 64-bit
  - Remove the open coded ASM entry code in 32-bit
  - Fix up the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202118.238455120@linutronix.de
2020-06-11 15:15:09 +02:00
Thomas Gleixner 49893c5cb2 x86/entry: Convert Invalid Opcode exception to IDTENTRY
Convert #UD to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Fixup the FOOF bug call in fault.c
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134904.955511913@linutronix.de
2020-06-11 15:14:47 +02:00
Thomas Gleixner ca4c6a9858 x86/traps: Make interrupt enable/disable symmetric in C code
Traps enable interrupts conditionally but rely on the ASM return code to
disable them again. That results in redundant interrupt disable and trace
calls.

Make the trap handlers disable interrupts before returning to avoid that,
which allows simplification of the ASM entry code in follow up changes.

Originally-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134903.622702796@linutronix.de
2020-06-11 15:14:42 +02:00
Christoph Hellwig 98a23609b1 maccess: always use strict semantics for probe_kernel_read
Except for historical confusion in the kprobes/uprobes and bpf tracers,
which has been fixed now, there is no good reason to ever allow user
memory accesses from probe_kernel_read.  Switch probe_kernel_read to only
read from kernel memory.

[akpm@linux-foundation.org: update it for "mm, dump_page(): do not crash with invalid mapping pointer"]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-17-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:15 -07:00
Christoph Hellwig eab0c6089b maccess: unify the probe kernel arch hooks
Currently architectures have to override every routine that probes
kernel memory, which includes a pure read and strcpy, both in strict
and not strict variants.  Just provide a single arch hooks instead to
make sure all architectures cover all the cases.

[akpm@linux-foundation.org: fix !CONFIG_X86_64 build]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-11-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:15 -07:00
Christoph Hellwig c4cb164426 maccess: rename strncpy_from_unsafe_strict to strncpy_from_kernel_nofault
This matches the naming of strncpy_from_user_nofault, and also makes it
more clear what the function is supposed to do.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-8-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:15 -07:00
Michel Lespinasse c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse da1c55f1b2 mmap locking API: rename mmap_sem to mmap_lock
Rename the mmap_sem field to mmap_lock.  Any new uses of this lock should
now go through the new mmap locking api.  The mmap_lock is still
implemented as a rwsem, though this could change in the future.

[akpm@linux-foundation.org: fix it for mm-gup-might_lock_readmmap_sem-in-get_user_pages_fast.patch]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-11-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Mike Rapoport e05c7b1f2b mm: pgtable: add shortcuts for accessing kernel PMD and PTE
The powerpc 32-bit implementation of pgtable has nice shortcuts for
accessing kernel PMD and PTE for a given virtual address.  Make these
helpers available for all architectures.

[rppt@linux.ibm.com: microblaze: fix page table traversal in setup_rt_frame()]
  Link: http://lkml.kernel.org/r/20200518191511.GD1118872@kernel.org
[akpm@linux-foundation.org: s/pmd_ptr_k/pmd_off_k/ in various powerpc places]

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-9-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport 88107d330d x86/mm: simplify init_trampoline() and surrounding logic
There are three cases for the trampoline initialization:
* 32-bit does nothing
* 64-bit with kaslr disabled simply copies a PGD entry from the direct map
  to the trampoline PGD
* 64-bit with kaslr enabled maps the real mode trampoline at PUD level

These cases are currently differentiated by a bunch of ifdefs inside
asm/include/pgtable.h and the case of 64-bits with kaslr on uses
pgd_index() helper.

Replacing the ifdefs with a static function in arch/x86/mm/init.c gives
clearer code and allows moving pgd_index() to the generic implementation
in include/linux/pgtable.h

[rppt@linux.ibm.com: take CONFIG_RANDOMIZE_MEMORY into account in kaslr_enabled()]
  Link: http://lkml.kernel.org/r/20200525104045.GB13212@linux.ibm.com

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-8-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport 65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport ca5999fde0 mm: introduce include/linux/pgtable.h
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport e31cf2f4ca mm: don't include asm/pgtable.h if linux/mm.h is already included
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include <linux/mm.h>") ; do
		sed -i -e '/include <asm\/pgtable.h>/ d' $f
	done

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Linus Torvalds f4dd60a3d4 Misc changes:
- Unexport various PAT primitives
 
  - Unexport per-CPU tlbstate
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl7Z+3cRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1jgyxAAjPoXEzi9rqGHY6Eus37DNbzHtdQj4fqN
 68h8T2tSnOMzETe3L/c4puxI50YFpMA0sFbzm8BfjCtucs0K7Tj4Sv8Aoap2b99A
 /bP+ySgHh2BMoI/tu9TiD8et+vttAGGwkXQhIOgeakZcYzpAY7oUNwc+CogkytbQ
 DaC8s9FL7RjCXCL91fvZ33C0ksg5J9ynFbRozEHOacHPrE3CbrqUwu+75PmS7nJC
 13vatOxjdqNPQhVMg7waN1nHv7K06kph1wxWxYHoD0QwAPy1ecE84wLvg9gv5AqK
 BfUBmB34qRW21qbB5tQrMlGDS9tuV0vUB1fxUV7/iOKXQUH6viEG/7J7jm+YwXji
 U9S54UPj/TOp8fvYdS18sp6vI1gS3HKjd3LO3pPHWsyZVMJBoGuMConZRs3C31Cp
 WuwBU1gY+mFB5l4prt8WU8ocPvEnZkP00cCYNyzPk21tblfUwFbrmu3wcZxOkx3s
 ZhRO4KrhxtL7l/wDLuNtWShBL2c6Rz2tts58tr/fj/M+UscJK2MPKxPLCAb20QYZ
 qSkMa36+r8LkuMCyjpegEEmo4sw9yC6aLXFKfYu2ABki5o9AR4tavk+lwO+dad6T
 k0DJjGXLsG9sReR6hrfaNTk5h7ImiRFDVntnWAhgKhARRoloJJS4/RkzW+ylPbac
 mTuNNJDChUQ=
 =RXKK
 -----END PGP SIGNATURE-----

Merge tag 'x86-mm-2020-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm updates from Ingo Molnar:
 "Misc changes:

   - Unexport various PAT primitives

   - Unexport per-CPU tlbstate and uninline TLB helpers"

* tag 'x86-mm-2020-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/tlb/uv: Add a forward declaration for struct flush_tlb_info
  x86/cpu: Export native_write_cr4() only when CONFIG_LKTDM=m
  x86/tlb: Restrict access to tlbstate
  xen/privcmd: Remove unneeded asm/tlb.h include
  x86/tlb: Move PCID helpers where they are used
  x86/tlb: Uninline nmi_uaccess_okay()
  x86/tlb: Move cr4_set_bits_and_update_boot() to the usage site
  x86/tlb: Move paravirt_tlb_remove_table() to the usage site
  x86/tlb: Move __flush_tlb_all() out of line
  x86/tlb: Move flush_tlb_others() out of line
  x86/tlb: Move __flush_tlb_one_kernel() out of line
  x86/tlb: Move __flush_tlb_one_user() out of line
  x86/tlb: Move __flush_tlb_global() out of line
  x86/tlb: Move __flush_tlb() out of line
  x86/alternatives: Move temporary_mm helpers into C
  x86/cr4: Sanitize CR4.PCE update
  x86/cpu: Uninline CR4 accessors
  x86/tlb: Uninline __get_current_cr3_fast()
  x86/mm: Use pgprotval_t in protval_4k_2_large() and protval_large_2_4k()
  x86/mm: Unexport __cachemode2pte_tbl
  ...
2020-06-05 11:18:53 -07:00
Ira Weiny abca2500c0 arch/kunmap_atomic: consolidate duplicate code
Every single architecture (including !CONFIG_HIGHMEM) calls...

	pagefault_enable();
	preempt_enable();

... before returning from __kunmap_atomic().  Lift this code into the
kunmap_atomic() macro.

While we are at it rename __kunmap_atomic() to kunmap_atomic_high() to
be consistent.

[ira.weiny@intel.com: don't enable pagefault/preempt twice]
  Link: http://lkml.kernel.org/r/20200518184843.3029640-1-ira.weiny@intel.com
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200507150004.1423069-8-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:22 -07:00