- Fix the I/O bitmap invalidation on XEN PV, which was overlooked in the
recent ioperm/iopl rework. This caused the TSS and XEN's I/O bitmap to
get out of sync.
- Use the proper vectors for HYPERV.
- Make disabling of stack protector for the entry code work with GCC
builds which enable stack protector by default. Removing the option is
not sufficient, it needs an explicit -fno-stack-protector to shut it
off.
- Mark check_user_regs() noinstr as it is called from noinstr code. The
missing annotation causes it to be placed in the text section which
makes it instrumentable.
- Add the missing interrupt disable in exc_alignment_check()
- Fixup a XEN_PV build dependency in the 32bit entry code
- A few fixes to make the Clang integrated assembler happy
- Move EFI stub build to the right place for out of tree builds
- Make prepare_exit_to_usermode() static. It's not longer called from ASM
code.
-----BEGIN PGP SIGNATURE-----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=QAeH
-----END PGP SIGNATURE-----
Merge tag 'x86-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull x86 fixes from Thomas Gleixner:
"A pile of fixes for x86:
- Fix the I/O bitmap invalidation on XEN PV, which was overlooked in
the recent ioperm/iopl rework. This caused the TSS and XEN's I/O
bitmap to get out of sync.
- Use the proper vectors for HYPERV.
- Make disabling of stack protector for the entry code work with GCC
builds which enable stack protector by default. Removing the option
is not sufficient, it needs an explicit -fno-stack-protector to
shut it off.
- Mark check_user_regs() noinstr as it is called from noinstr code.
The missing annotation causes it to be placed in the text section
which makes it instrumentable.
- Add the missing interrupt disable in exc_alignment_check()
- Fixup a XEN_PV build dependency in the 32bit entry code
- A few fixes to make the Clang integrated assembler happy
- Move EFI stub build to the right place for out of tree builds
- Make prepare_exit_to_usermode() static. It's not longer called from
ASM code"
* tag 'x86-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Don't add the EFI stub to targets
x86/entry: Actually disable stack protector
x86/ioperm: Fix io bitmap invalidation on Xen PV
x86: math-emu: Fix up 'cmp' insn for clang ias
x86/entry: Fix vectors to IDTENTRY_SYSVEC for CONFIG_HYPERV
x86/entry: Add compatibility with IAS
x86/entry/common: Make prepare_exit_to_usermode() static
x86/entry: Mark check_user_regs() noinstr
x86/traps: Disable interrupts in exc_aligment_check()
x86/entry/32: Fix XEN_PV build dependency
tss_invalidate_io_bitmap() wasn't wired up properly through the pvop
machinery, so the TSS and Xen's io bitmap would get out of sync
whenever disabling a valid io bitmap.
Add a new pvop for tss_invalidate_io_bitmap() to fix it.
This is XSA-329.
Fixes: 22fe5b0439 ("x86/ioperm: Move TSS bitmap update to exit to user work")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/d53075590e1f91c19f8af705059d3ff99424c020.1595030016.git.luto@kernel.org
IOSF MBI header contains a lot of definitions, such as
end point addresses of IPs. Move CCK address from AtomISP driver
to generic header.
While here, drop unused one.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
With UV1 support removed, EFI_UV1_MEMMAP is no longer used.
Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lkml.kernel.org/r/20200713212956.019149227@hpe.com
When assembling with Clang via `make LLVM_IAS=1` and CONFIG_HYPERV enabled,
we observe the following error:
<instantiation>:9:6: error: expected absolute expression
.if HYPERVISOR_REENLIGHTENMENT_VECTOR == 3
^
<instantiation>:1:1: note: while in macro instantiation
idtentry HYPERVISOR_REENLIGHTENMENT_VECTOR asm_sysvec_hyperv_reenlightenment sysvec_hyperv_reenlightenment has_error_code=0
^
./arch/x86/include/asm/idtentry.h:627:1: note: while in macro instantiation
idtentry_sysvec HYPERVISOR_REENLIGHTENMENT_VECTOR sysvec_hyperv_reenlightenment;
^
<instantiation>:9:6: error: expected absolute expression
.if HYPERVISOR_STIMER0_VECTOR == 3
^
<instantiation>:1:1: note: while in macro instantiation
idtentry HYPERVISOR_STIMER0_VECTOR asm_sysvec_hyperv_stimer0 sysvec_hyperv_stimer0 has_error_code=0
^
./arch/x86/include/asm/idtentry.h:628:1: note: while in macro instantiation
idtentry_sysvec HYPERVISOR_STIMER0_VECTOR sysvec_hyperv_stimer0;
This is caused by typos in arch/x86/include/asm/idtentry.h:
HYPERVISOR_REENLIGHTENMENT_VECTOR -> HYPERV_REENLIGHTENMENT_VECTOR
HYPERVISOR_STIMER0_VECTOR -> HYPERV_STIMER0_VECTOR
For more details see ClangBuiltLinux issue #1088.
Fixes: a16be368dd ("x86/entry: Convert various hypervisor vectors to IDTENTRY_SYSVEC")
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1088
Link: https://github.com/ClangBuiltLinux/linux/issues/1043
Link: https://lore.kernel.org/patchwork/patch/1272115/
Link: https://lkml.kernel.org/r/20200714194740.4548-1-sedat.dilek@gmail.com
Clang's integrated assembler does not allow symbols with non-absolute
values to be reassigned. Modify the interrupt entry loop macro to be
compatible with IAS by using a label and an offset.
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Suggested-by: Brian Gerst <brgerst@gmail.com>
Suggested-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Jian Cai <caij2003@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> #
Link: https://github.com/ClangBuiltLinux/linux/issues/1043
Link: https://lkml.kernel.org/r/20200714233024.1789985-1-caij2003@gmail.com
Current minimum required version of binutils is 2.23,
which supports PSHUFB, PCLMULQDQ, PEXTRD, AESKEYGENASSIST,
AESIMC, AESENC, AESENCLAST, AESDEC, AESDECLAST and MOVQ
instruction mnemonics.
Substitute macros from include/asm/inst.h with a proper
instruction mnemonics in various assmbly files from
x86/crypto directory, and remove now unneeded file.
The patch was tested by calculating and comparing sha256sum
hashes of stripped object files before and after the patch,
to be sure that executable code didn't change.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: "David S. Miller" <davem@davemloft.net>
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>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stack switching for interrupt handlers happens in C now for both 64 and
32bit. Remove the stale comment which claims the contrary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds a new capability KVM_CAP_SMALLER_MAXPHYADDR which
allows userspace to query if the underlying architecture would
support GUEST_MAXPHYADDR < HOST_MAXPHYADDR and hence act accordingly
(e.g. qemu can decide if it should warn for -cpu ..,phys-bits=X)
The complications in this patch are due to unexpected (but documented)
behaviour we see with NPF vmexit handling in AMD processor. If
SVM is modified to add guest physical address checks in the NPF
and guest #PF paths, we see the followning error multiple times in
the 'access' test in kvm-unit-tests:
test pte.p pte.36 pde.p: FAIL: pte 2000021 expected 2000001
Dump mapping: address: 0x123400000000
------L4: 24c3027
------L3: 24c4027
------L2: 24c5021
------L1: 1002000021
This is because the PTE's accessed bit is set by the CPU hardware before
the NPF vmexit. This is handled completely by hardware and cannot be fixed
in software.
Therefore, availability of the new capability depends on a boolean variable
allow_smaller_maxphyaddr which is set individually by VMX and SVM init
routines. On VMX it's always set to true, on SVM it's only set to true
when NPT is not enabled.
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Babu Moger <babu.moger@amd.com>
Signed-off-by: Mohammed Gamal <mgamal@redhat.com>
Message-Id: <20200710154811.418214-10-mgamal@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We would like to introduce a callback to update the #PF intercept
when CPUID changes. Just reuse update_bp_intercept since VMX is
already using update_exception_bitmap instead of a bespoke function.
While at it, remove an unnecessary assignment in the SVM version,
which is already done in the caller (kvm_arch_vcpu_ioctl_set_guest_debug)
and has nothing to do with the exception bitmap.
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Also no point of it being inline since it's always called through
function pointers. So remove that.
Signed-off-by: Mohammed Gamal <mgamal@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200710154811.418214-3-mgamal@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl8IQ20UHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroNzxQf+KziWiVgLYnRmGVJ4xztRGv8Cjt+o
g1YRyJgpST4UEdHyO+T1JvO8HVzTxtDwZlRNHB9UtIaAsAuybSdpUaHeK9lvcZvi
vd59ItmyHKFOtItfG6Qpj6MJKN9tbN1y2F9Vc+TXNLL9BLHwPTbvF3l5ffdtBJ6F
zurQBec7hoCarXZJS2GfzBQ+16WxZmm7RLDpYtEqAayp+UHNw+Z1eMrMV6TwdxAA
3LgDn3l+A+BNuIIUKFF9Y5Ef3T4zBWGbdsV7FR9mH1fq2DiT1Vz4IT674L+6rEom
/KvyyjVPIfQF33sMZmVpLCpoe2IEmOtc7cu3zffqNL6gNw3YHZwMK6cgsg==
=abJa
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull vkm fixes from Paolo Bonzini:
"Two simple but important bugfixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: MIPS: Fix build errors for 32bit kernel
KVM: nVMX: fixes for preemption timer migration
Commit 850448f35a ("KVM: nVMX: Fix VMX preemption timer migration",
2020-06-01) accidentally broke nVMX live migration from older version
by changing the userspace ABI. Restore it and, while at it, ensure
that vmx->nested.has_preemption_timer_deadline is always initialized
according to the KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE flag.
Cc: Makarand Sonare <makarandsonare@google.com>
Fixes: 850448f35a ("KVM: nVMX: Fix VMX preemption timer migration")
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While the nmi_enter() users did
trace_hardirqs_{off_prepare,on_finish}() there was no matching
lockdep_hardirqs_*() calls to complete the picture.
Introduce idtentry_{enter,exit}_nmi() to enable proper IRQ state
tracking across the NMIs.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200623083721.216740948@infradead.org
Move x86's 'struct kvm_mmu_memory_cache' to common code in anticipation
of moving the entire x86 implementation code to common KVM and reusing
it for arm64 and MIPS. Add a new architecture specific asm/kvm_types.h
to control the existence and parameters of the struct. The new header
is needed to avoid a chicken-and-egg problem with asm/kvm_host.h as all
architectures define instances of the struct in their vCPU structs.
Add an asm-generic version of kvm_types.h to avoid having empty files on
PPC and s390 in the long term, and for arm64 and mips in the short term.
Suggested-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200703023545.8771-15-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a gfp_zero flag to 'struct kvm_mmu_memory_cache' and use it to
control __GFP_ZERO instead of hardcoding a call to kmem_cache_zalloc().
A future patch needs such a flag for the __get_free_page() path, as
gfn arrays do not need/want the allocator to zero the memory. Convert
the kmem_cache paths to __GFP_ZERO now so as to avoid a weird and
inconsistent API in the future.
No functional change intended.
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200703023545.8771-11-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use separate caches for allocating shadow pages versus gfn arrays. This
sets the stage for specifying __GFP_ZERO when allocating shadow pages
without incurring extra cost for gfn arrays.
No functional change intended.
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200703023545.8771-10-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Track the kmem_cache used for non-page KVM MMU memory caches instead of
passing in the associated kmem_cache when filling the cache. This will
allow consolidating code and other cleanups.
No functional change intended.
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200703023545.8771-2-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the functions which are inside the RCU off region into the
non-instrumentable text section.
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: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200708195322.037311579@linutronix.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The name of callback cpuid_update() is misleading that it's not about
updating CPUID settings of vcpu but updating the configurations of vcpu
based on the CPUIDs. So rename it to vcpu_after_set_cpuid().
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20200709043426.92712-5-xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of creating the mask for guest CR4 reserved bits in kvm_valid_cr4(),
do it in kvm_update_cpuid() so that it can be reused instead of creating it
each time kvm_valid_cr4() is called.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <1594168797-29444-2-git-send-email-krish.sadhukhan@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are cases where a guest tries to switch spinlocks to bare metal
behavior (e.g. by setting "xen_nopvspin" on XEN platform and
"hv_nopvspin" on HYPER_V).
That feature is missed on KVM, add a new parameter "nopvspin" to disable
PV spinlocks for KVM guest.
The new 'nopvspin' parameter will also replace Xen and Hyper-V specific
parameters in future patches.
Define variable nopvsin as global because it will be used in future
patches as above.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
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: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make 'struct kvm_mmu_page' MMU-only, nothing outside of the MMU should
be poking into the gory details of shadow pages.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200622202034.15093-5-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Current minimum required version of binutils is 2.23,
which supports VMCALL and VMMCALL instruction mnemonics.
Replace the byte-wise specification of VMCALL and
VMMCALL with these proper mnemonics.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200623183439.5526-1-ubizjak@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Both the vcpu_vmx structure and the vcpu_svm structure have a
'last_cpu' field. Move the common field into the kvm_vcpu_arch
structure. For clarity, rename it to 'last_vmentry_cpu.'
Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Message-Id: <20200603235623.245638-6-jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move .write_log_dirty() into kvm_x86_nested_ops to help differentiate it
from the non-nested dirty log hooks. And because it's a nested-only
operation.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200622215832.22090-5-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the LBR call stack mode, LBR information is used to reconstruct a
call stack. To get the complete call stack, perf has to save/restore
all LBR registers during a context switch. Due to a large number of the
LBR registers, this process causes a high CPU overhead. To reduce the
CPU overhead during a context switch, use the XSAVES/XRSTORS
instructions.
Every XSAVE area must follow a canonical format: the legacy region, an
XSAVE header and the extended region. Although the LBR information is
only kept in the extended region, a space for the legacy region and
XSAVE header is still required. Add a new dedicated structure for LBR
XSAVES support.
Before enabling XSAVES support, the size of the LBR state has to be
sanity checked, because:
- the size of the software structure is calculated from the max number
of the LBR depth, which is enumerated by the CPUID leaf for Arch LBR.
The size of the LBR state is enumerated by the CPUID leaf for XSAVE
support of Arch LBR. If the values from the two CPUID leaves are not
consistent, it may trigger a buffer overflow. For example, a hypervisor
may unconsciously set inconsistent values for the two emulated CPUID.
- unlike other state components, the size of an LBR state depends on the
max number of LBRs, which may vary from generation to generation.
Expose the function xfeature_size() for the sanity check.
The LBR XSAVES support will be disabled if the size of the LBR state
enumerated by CPUID doesn't match with the size of the software
structure.
The XSAVE instruction requires 64-byte alignment for state buffers. A
new macro is added to reflect the alignment requirement. A 64-byte
aligned kmem_cache is created for architecture LBR.
Currently, the structure for each state component is maintained in
fpu/types.h. The structure for the new LBR state component should be
maintained in the same place. Move structure lbr_entry to fpu/types.h as
well for broader sharing.
Add dedicated lbr_save/lbr_restore functions for LBR XSAVES support,
which invokes the corresponding xstate helpers to XSAVES/XRSTORS LBR
information at the context switch when the call stack mode is enabled.
Since the XSAVES/XRSTORS instructions will be eventually invoked, the
dedicated functions is named with '_xsaves'/'_xrstors' postfix.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/1593780569-62993-23-git-send-email-kan.liang@linux.intel.com
The perf subsystem will only need to save/restore the LBR state.
However, the existing helpers save all supported supervisor states to a
kernel buffer, which will be unnecessary. Two helpers are introduced to
only save/restore requested dynamic supervisor states. The supervisor
features in XFEATURE_MASK_SUPERVISOR_SUPPORTED and
XFEATURE_MASK_SUPERVISOR_UNSUPPORTED mask cannot be saved/restored using
these helpers.
The helpers will be used in the following patch.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/1593780569-62993-22-git-send-email-kan.liang@linux.intel.com
Last Branch Records (LBR) registers are used to log taken branches and
other control flows. In perf with call stack mode, LBR information is
used to reconstruct a call stack. To get the complete call stack, perf
has to save/restore all LBR registers during a context switch. Due to
the large number of the LBR registers, e.g., the current platform has
96 LBR registers, this process causes a high CPU overhead. To reduce
the CPU overhead during a context switch, an LBR state component that
contains all the LBR related registers is introduced in hardware. All
LBR registers can be saved/restored together using one XSAVES/XRSTORS
instruction.
However, the kernel should not save/restore the LBR state component at
each context switch, like other state components, because of the
following unique features of LBR:
- The LBR state component only contains valuable information when LBR
is enabled in the perf subsystem, but for most of the time, LBR is
disabled.
- The size of the LBR state component is huge. For the current
platform, it's 808 bytes.
If the kernel saves/restores the LBR state at each context switch, for
most of the time, it is just a waste of space and cycles.
To efficiently support the LBR state component, it is desired to have:
- only context-switch the LBR when the LBR feature is enabled in perf.
- only allocate an LBR-specific XSAVE buffer on demand.
(Besides the LBR state, a legacy region and an XSAVE header have to be
included in the buffer as well. There is a total of (808+576) byte
overhead for the LBR-specific XSAVE buffer. The overhead only happens
when the perf is actively using LBRs. There is still a space-saving,
on average, when it replaces the constant 808 bytes of overhead for
every task, all the time on the systems that support architectural
LBR.)
- be able to use XSAVES/XRSTORS for accessing LBR at run time.
However, the IA32_XSS should not be adjusted at run time.
(The XCR0 | IA32_XSS are used to determine the requested-feature
bitmap (RFBM) of XSAVES.)
A solution, called dynamic supervisor feature, is introduced to address
this issue, which
- does not allocate a buffer in each task->fpu;
- does not save/restore a state component at each context switch;
- sets the bit corresponding to the dynamic supervisor feature in
IA32_XSS at boot time, and avoids setting it at run time.
- dynamically allocates a specific buffer for a state component
on demand, e.g. only allocates LBR-specific XSAVE buffer when LBR is
enabled in perf. (Note: The buffer has to include the LBR state
component, a legacy region and a XSAVE header space.)
(Implemented in a later patch)
- saves/restores a state component on demand, e.g. manually invokes
the XSAVES/XRSTORS instruction to save/restore the LBR state
to/from the buffer when perf is active and a call stack is required.
(Implemented in a later patch)
A new mask XFEATURE_MASK_DYNAMIC and a helper xfeatures_mask_dynamic()
are introduced to indicate the dynamic supervisor feature. For the
systems which support the Architecture LBR, LBR is the only dynamic
supervisor feature for now. For the previous systems, there is no
dynamic supervisor feature available.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/1593780569-62993-21-git-send-email-kan.liang@linux.intel.com
When saving xstate to a kernel/user XSAVE area with the XSAVE family of
instructions, the current code applies the 'full' instruction mask (-1),
which tries to XSAVE all possible features. This method relies on
hardware to trim 'all possible' down to what is enabled in the
hardware. The code works well for now. However, there will be a
problem, if some features are enabled in hardware, but are not suitable
to be saved into all kernel XSAVE buffers, like task->fpu, due to
performance consideration.
One such example is the Last Branch Records (LBR) state. The LBR state
only contains valuable information when LBR is explicitly enabled by
the perf subsystem, and the size of an LBR state is large (808 bytes
for now). To avoid both CPU overhead and space overhead at each context
switch, the LBR state should not be saved into task->fpu like other
state components. It should be saved/restored on demand when LBR is
enabled in the perf subsystem. Current copy_xregs_to_* will trigger a
buffer overflow for such cases.
Three sites use the '-1' instruction mask which must be updated.
Two are saving/restoring the xstate to/from a kernel-allocated XSAVE
buffer and can use 'xfeatures_mask_all', which will save/restore all of
the features present in a normal task FPU buffer.
The last one saves the register state directly to a user buffer. It
could
also use 'xfeatures_mask_all'. Just as it was with the '-1' argument,
any supervisor states in the mask will be filtered out by the hardware
and not saved to the buffer. But, to be more explicit about what is
expected to be saved, use xfeatures_mask_user() for the instruction
mask.
KVM includes the header file fpu/internal.h. To avoid 'undefined
xfeatures_mask_all' compiling issue, move copy_fpregs_to_fpstate() to
fpu/core.c and export it, because:
- The xfeatures_mask_all is indirectly used via copy_fpregs_to_fpstate()
by KVM. The function which is directly used by other modules should be
exported.
- The copy_fpregs_to_fpstate() is a function, while xfeatures_mask_all
is a variable for the "internal" FPU state. It's safer to export a
function than a variable, which may be implicitly changed by others.
- The copy_fpregs_to_fpstate() is a big function with many checks. The
removal of the inline keyword should not impact the performance.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/1593780569-62993-20-git-send-email-kan.liang@linux.intel.com
Current LBR information in the structure x86_perf_task_context is stored
in a different format from the PEBS LBR record and Architecture LBR,
which prevents the sharing of the common codes.
Use the format of the PEBS LBR record as a unified format. Use a generic
name lbr_entry to replace pebs_lbr_entry.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-11-git-send-email-kan.liang@linux.intel.com
The LBR capabilities of Architecture LBR are retrieved from the CPUID
enumeration once at boot time. The capabilities have to be saved for
future usage.
Several new fields are added into structure x86_pmu to indicate the
capabilities. The fields will be used in the following patches.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-9-git-send-email-kan.liang@linux.intel.com
CPUID.(EAX=07H, ECX=0):EDX[19] indicates whether an Intel CPU supports
Architectural LBRs.
The "X86_FEATURE_..., word 18" is already mirrored from CPUID
"0x00000007:0 (EDX)". Add X86_FEATURE_ARCH_LBR under the "word 18"
section.
The feature will appear as "arch_lbr" in /proc/cpuinfo.
The Architectural Last Branch Records (LBR) feature enables recording
of software path history by logging taken branches and other control
flows. The feature will be supported in the perf_events subsystem.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lkml.kernel.org/r/1593780569-62993-2-git-send-email-kan.liang@linux.intel.com
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
xenpv_exc_nmi() and xenpv_exc_debug() are only defined on 64-bit kernels,
but they snuck into the 32-bit build via <asm/identry.h>, causing the link
to fail:
ld: arch/x86/entry/entry_32.o: in function `asm_xenpv_exc_nmi':
(.entry.text+0x817): undefined reference to `xenpv_exc_nmi'
ld: arch/x86/entry/entry_32.o: in function `asm_xenpv_exc_debug':
(.entry.text+0x827): undefined reference to `xenpv_exc_debug'
Only use them on 64-bit kernels.
Fixes: f41f0824224e: ("x86/entry/xen: Route #DB correctly on Xen PV")
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Reset MXCSR in kernel_fpu_begin() to prevent using a stale user space
value.
- Prevent writing MSR_TEST_CTRL on CPUs which are not explicitly
whitelisted for split lock detection. Some CPUs which do not support
it crash even when the MSR is written to 0 which is the default value.
- Fix the XEN PV fallout of the entry code rework
- Fix the 32bit fallout of the entry code rework
- Add more selftests to ensure that these entry problems don't come back.
- Disable 16 bit segments on XEN PV. It's not supported because XEN PV
does not implement ESPFIX64
-----BEGIN PGP SIGNATURE-----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=lI9c
-----END PGP SIGNATURE-----
Merge tag 'x86-urgent-2020-07-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"A series of fixes for x86:
- Reset MXCSR in kernel_fpu_begin() to prevent using a stale user
space value.
- Prevent writing MSR_TEST_CTRL on CPUs which are not explicitly
whitelisted for split lock detection. Some CPUs which do not
support it crash even when the MSR is written to 0 which is the
default value.
- Fix the XEN PV fallout of the entry code rework
- Fix the 32bit fallout of the entry code rework
- Add more selftests to ensure that these entry problems don't come
back.
- Disable 16 bit segments on XEN PV. It's not supported because XEN
PV does not implement ESPFIX64"
* tag 'x86-urgent-2020-07-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ldt: Disable 16-bit segments on Xen PV
x86/entry/32: Fix #MC and #DB wiring on x86_32
x86/entry/xen: Route #DB correctly on Xen PV
x86/entry, selftests: Further improve user entry sanity checks
x86/entry/compat: Clear RAX high bits on Xen PV SYSENTER
selftests/x86: Consolidate and fix get/set_eflags() helpers
selftests/x86/syscall_nt: Clear weird flags after each test
selftests/x86/syscall_nt: Add more flag combinations
x86/entry/64/compat: Fix Xen PV SYSENTER frame setup
x86/entry: Move SYSENTER's regs->sp and regs->flags fixups into C
x86/entry: Assert that syscalls are on the right stack
x86/split_lock: Don't write MSR_TEST_CTRL on CPUs that aren't whitelisted
x86/fpu: Reset MXCSR to default in kernel_fpu_begin()
DEFINE_IDTENTRY_MCE and DEFINE_IDTENTRY_DEBUG were wired up as non-RAW
on x86_32, but the code expected them to be RAW.
Get rid of all the macro indirection for them on 32-bit and just use
DECLARE_IDTENTRY_RAW and DEFINE_IDTENTRY_RAW directly.
Also add a warning to make sure that we only hit the _kernel paths
in kernel mode.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
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/9e90a7ee8e72fd757db6d92e1e5ff16339c1ecf9.1593795633.git.luto@kernel.org
On Xen PV, #DB doesn't use IST. It still needs to be correctly routed
depending on whether it came from user or kernel mode.
Get rid of DECLARE/DEFINE_IDTENTRY_XEN -- it was too hard to follow the
logic. Instead, route #DB and NMI through DECLARE/DEFINE_IDTENTRY_RAW on
Xen, and do the right thing for #DB. Also add more warnings to the
exc_debug* handlers to make this type of failure more obvious.
This fixes various forms of corruption that happen when usermode
triggers #DB on Xen PV.
Fixes: 4c0dcd8350 ("x86/entry: Implement user mode C entry points for #DB and #MCE")
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/4163e733cce0b41658e252c6c6b3464f33fdff17.1593795633.git.luto@kernel.org
The hypervisor may request the perf subsystem to schedule a time window
to directly access the LBR records msrs for its own use. Normally, it would
create a guest LBR event with callstack mode enabled, which is scheduled
along with other ordinary LBR events on the host but in an exclusive way.
To avoid wasting a counter for the guest LBR event, the perf tracks its
hw->idx via INTEL_PMC_IDX_FIXED_VLBR and assigns it with a fake VLBR
counter with the help of new vlbr_constraint. As with the BTS event,
there is actually no hardware counter assigned for the guest LBR event.
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200514083054.62538-5-like.xu@linux.intel.com
The LBR records msrs are model specific. The perf subsystem has already
obtained the base addresses of LBR records based on the cpu model.
Therefore, an interface is added to allow callers outside the perf
subsystem to obtain these LBR information. It's useful for hypervisors
to emulate the LBR feature for guests with less code.
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200613080958.132489-4-like.xu@linux.intel.com
By default intel_pstate the driver disables energy efficiency by setting
MSR_IA32_POWER_CTL bit 19 for Kaby Lake desktop CPU model in HWP mode.
This CPU model is also shared by Coffee Lake desktop CPUs. This allows
these systems to reach maximum possible frequency. But this adds power
penalty, which some customers don't want. They want some way to enable/
disable dynamically.
So, add an additional attribute "energy_efficiency" under
/sys/devices/system/cpu/intel_pstate/ for these CPU models. This allows
to read and write bit 19 ("Disable Energy Efficiency Optimization") in
the MSR IA32_POWER_CTL.
This attribute is present in both HWP and non-HWP mode as this has an
effect in both modes. Refer to Intel Software Developer's manual for
details.
The scope of this bit is package wide. Also these systems are single
package systems. So read/write MSR on the current CPU is enough.
The energy efficiency (EE) bit setting needs to be preserved during
suspend/resume and CPU offline/online operation. To do this:
- Restoring the EE setting from the cpufreq resume() callback, if there
is change from the system default.
- By default, don't disable EE from cpufreq init() callback for matching
CPU models. Since the scope is package wide and is a single package
system, move the disable EE calls from init() callback to
intel_pstate_init() function, which is called only once.
Suggested-by: Len Brown <lenb@kernel.org>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Debuggers expect that doing PTRACE_GETREGS, then poking at a tracee
and maybe letting it run for a while, then doing PTRACE_SETREGS will
put the tracee back where it was. In the specific case of a 32-bit
tracer and tracee, the PTRACE_GETREGS/SETREGS data structure doesn't
have fs_base or gs_base fields, so FSBASE and GSBASE fields are
never stored anywhere. Everything used to still work because
nonzero FS or GS would result full reloads of the segment registers
when the tracee resumes, and the bases associated with FS==0 or
GS==0 are irrelevant to 32-bit code.
Adding FSGSBASE support broke this: when FSGSBASE is enabled, FSBASE
and GSBASE are now restored independently of FS and GS for all tasks
when context-switched in. This means that, if a 32-bit tracer
restores a previous state using PTRACE_SETREGS but the tracee's
pre-restore and post-restore bases don't match, then the tracee is
resumed with the wrong base.
Fix it by explicitly loading the base when a 32-bit tracer pokes FS
or GS on a 64-bit kernel.
Also add a test case.
Fixes: 673903495c ("x86/process/64: Use FSBSBASE in switch_to() if available")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/229cc6a50ecbb701abd50fe4ddaf0eda888898cd.1593192140.git.luto@kernel.org
There are no users left, all drivers have been converted to use the
per-device private pointer offered by IOMMU core.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200625130836.1916-10-joro@8bytes.org
Previously, kernel floating point code would run with the MXCSR control
register value last set by userland code by the thread that was active
on the CPU core just before kernel call. This could affect calculation
results if rounding mode was changed, or a crash if a FPU/SIMD exception
was unmasked.
Restore MXCSR to the kernel's default value.
[ bp: Carve out from a bigger patch by Petteri, add feature check, add
FNINIT call too (amluto). ]
Signed-off-by: Petteri Aimonen <jpa@git.mail.kapsi.fi>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=207979
Link: https://lkml.kernel.org/r/20200624114646.28953-2-bp@alien8.de
* Use the proper length type in the 32-bit truncate() syscall variant,
by Jiri Slaby.
* Reinit IA32_FEAT_CTL during wakeup to fix the case where after
resume, VMXON would #GP due to VMX not being properly enabled, by Sean
Christopherson.
* Fix a static checker warning in the resctrl code, by Dan Carpenter.
* Add a CR4 pinning mask for bits which cannot change after boot, by
Kees Cook.
* Align the start of the loop of __clear_user() to 16 bytes, to improve
performance on AMD zen1 and zen2 microarchitectures, by Matt Fleming.
-----BEGIN PGP SIGNATURE-----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=hxkd
-----END PGP SIGNATURE-----
Merge tag 'x86_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- AMD Memory bandwidth counter width fix, by Babu Moger.
- Use the proper length type in the 32-bit truncate() syscall variant,
by Jiri Slaby.
- Reinit IA32_FEAT_CTL during wakeup to fix the case where after
resume, VMXON would #GP due to VMX not being properly enabled, by
Sean Christopherson.
- Fix a static checker warning in the resctrl code, by Dan Carpenter.
- Add a CR4 pinning mask for bits which cannot change after boot, by
Kees Cook.
- Align the start of the loop of __clear_user() to 16 bytes, to improve
performance on AMD zen1 and zen2 microarchitectures, by Matt Fleming.
* tag 'x86_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm/64: Align start of __clear_user() loop to 16-bytes
x86/cpu: Use pinning mask for CR4 bits needing to be 0
x86/resctrl: Fix a NULL vs IS_ERR() static checker warning in rdt_cdp_peer_get()
x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
syscalls: Fix offset type of ksys_ftruncate()
x86/resctrl: Fix memory bandwidth counter width for AMD
These patches address a number of instrumentation issues that were found after
the x86/entry overhaul. When combined with rcu/urgent and objtool/urgent, these
patches make UBSAN/KASAN/KCSAN happy again.
Part of making this all work is bumping the minimum GCC version for KASAN
builds to gcc-8.3, the reason for this is that the __no_sanitize_address
function attribute is broken in GCC releases before that.
No known GCC version has a working __no_sanitize_undefined, however because the
only noinstr violation that results from this happens when an UB is found, we
treat it like WARN. That is, we allow it to violate the noinstr rules in order
to get the warning out.
-----BEGIN PGP SIGNATURE-----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=fcu1
-----END PGP SIGNATURE-----
Merge tag 'x86_entry_for_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 entry fixes from Borislav Petkov:
"This is the x86/entry urgent pile which has accumulated since the
merge window.
It is not the smallest but considering the almost complete entry core
rewrite, the amount of fixes to follow is somewhat higher than usual,
which is to be expected.
Peter Zijlstra says:
'These patches address a number of instrumentation issues that were
found after the x86/entry overhaul. When combined with rcu/urgent
and objtool/urgent, these patches make UBSAN/KASAN/KCSAN happy
again.
Part of making this all work is bumping the minimum GCC version for
KASAN builds to gcc-8.3, the reason for this is that the
__no_sanitize_address function attribute is broken in GCC releases
before that.
No known GCC version has a working __no_sanitize_undefined, however
because the only noinstr violation that results from this happens
when an UB is found, we treat it like WARN. That is, we allow it to
violate the noinstr rules in order to get the warning out'"
* tag 'x86_entry_for_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry: Fix #UD vs WARN more
x86/entry: Increase entry_stack size to a full page
x86/entry: Fixup bad_iret vs noinstr
objtool: Don't consider vmlinux a C-file
kasan: Fix required compiler version
compiler_attributes.h: Support no_sanitize_undefined check with GCC 4
x86/entry, bug: Comment the instrumentation_begin() usage for WARN()
x86/entry, ubsan, objtool: Whitelist __ubsan_handle_*()
x86/entry, cpumask: Provide non-instrumented variant of cpu_is_offline()
compiler_types.h: Add __no_sanitize_{address,undefined} to noinstr
kasan: Bump required compiler version
x86, kcsan: Add __no_kcsan to noinstr
kcsan: Remove __no_kcsan_or_inline
x86, kcsan: Remove __no_kcsan_or_inline usage
Patch series "fix a hyperv W^X violation and remove vmalloc_exec"
Dexuan reported a W^X violation due to the fact that the hyper hypercall
page due switching it to be allocated using vmalloc_exec.
The problem is that PAGE_KERNEL_EXEC as used by vmalloc_exec actually
sets writable permissions in the pte. This series fixes the issue by
switching to the low-level __vmalloc_node_range interface that allows
specifing more detailed permissions instead. It then also open codes
the other two callers and removes the somewhat confusing vmalloc_exec
interface.
Peter noted that the hyper hypercall page allocation also has another
long standing issue in that it shouldn't use the full vmalloc but just
the module space. This issue is so far theoretical as the allocation is
done early in the boot process. I plan to fix it with another bigger
series for 5.9.
This patch (of 3):
Avoid a W^X violation cause by the fact that PAGE_KERNEL_EXEC includes
the writable bit.
For this resurrect the removed PAGE_KERNEL_RX definition, but as
PAGE_KERNEL_ROX to match arm64 and powerpc.
Link: http://lkml.kernel.org/r/20200618064307.32739-2-hch@lst.de
Fixes: 78bb17f76e ("x86/hyperv: use vmalloc_exec for the hypercall page")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Dexuan Cui <decui@microsoft.com>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marco crashed in bad_iret with a Clang11/KCSAN build due to
overflowing the stack. Now that we run C code on it, expand it to a
full page.
Suggested-by: Andy Lutomirski <luto@amacapital.net>
Reported-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200618144801.819246178@infradead.org
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl7x2lwUHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroPiVAgAn/83Vx/YrF9sr0+TLzukzfOubJVK
Majxb0I06De23VDExiDoZjh5CnCN3kDja0m2c543ZI1XOrHRbp09v1goJQkAgiT0
AQ8Npi1KB71io18SbZtrAhPLmSiUgRirF+XWHB38qjdbZixvZyWz8nvSITFY8aJQ
ICgbm5jftzBdSOKEhqbHwZ+LcXjEGZsehwTiHpUBKUR/kNlRFV5UFAd5m+CT5i4O
3DydLIReATDCoZUKfkBjYtoR3c9DyWESyfWD4GZ/2xRKr/1QfiZ4dA0cd/P9hJYz
7MAG+ULvJGlasSzmcEQJ/X3o9QuIJzpQFpwbKeMX6gOsEsSVUQeriUHIFA==
=jTFw
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"All bugfixes except for a couple cleanup patches"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: VMX: Remove vcpu_vmx's defunct copy of host_pkru
KVM: x86: allow TSC to differ by NTP correction bounds without TSC scaling
KVM: X86: Fix MSR range of APIC registers in X2APIC mode
KVM: VMX: Stop context switching MSR_IA32_UMWAIT_CONTROL
KVM: nVMX: Plumb L2 GPA through to PML emulation
KVM: x86/mmu: Avoid mixing gpa_t with gfn_t in walk_addr_generic()
KVM: LAPIC: ensure APIC map is up to date on concurrent update requests
kvm: lapic: fix broken vcpu hotplug
Revert "KVM: VMX: Micro-optimize vmexit time when not exposing PMU"
KVM: VMX: Add helpers to identify interrupt type from intr_info
kvm/svm: disable KCSAN for svm_vcpu_run()
KVM: MIPS: Fix a build error for !CPU_LOONGSON64
Remove support for context switching between the guest's and host's
desired UMWAIT_CONTROL. Propagating the guest's value to hardware isn't
required for correct functionality, e.g. KVM intercepts reads and writes
to the MSR, and the latency effects of the settings controlled by the
MSR are not architecturally visible.
As a general rule, KVM should not allow the guest to control power
management settings unless explicitly enabled by userspace, e.g. see
KVM_CAP_X86_DISABLE_EXITS. E.g. Intel's SDM explicitly states that C0.2
can improve the performance of SMT siblings. A devious guest could
disable C0.2 so as to improve the performance of their workloads at the
detriment to workloads running in the host or on other VMs.
Wholesale removal of UMWAIT_CONTROL context switching also fixes a race
condition where updates from the host may cause KVM to enter the guest
with the incorrect value. Because updates are are propagated to all
CPUs via IPI (SMP function callback), the value in hardware may be
stale with respect to the cached value and KVM could enter the guest
with the wrong value in hardware. As above, the guest can't observe the
bad value, but it's a weird and confusing wart in the implementation.
Removal also fixes the unnecessary usage of VMX's atomic load/store MSR
lists. Using the lists is only necessary for MSRs that are required for
correct functionality immediately upon VM-Enter/VM-Exit, e.g. EFER on
old hardware, or for MSRs that need to-the-uop precision, e.g. perf
related MSRs. For UMWAIT_CONTROL, the effects are only visible in the
kernel via TPAUSE/delay(), and KVM doesn't do any form of delay in
vcpu_vmx_run(). Using the atomic lists is undesirable as they are more
expensive than direct RDMSR/WRMSR.
Furthermore, even if giving the guest control of the MSR is legitimate,
e.g. in pass-through scenarios, it's not clear that the benefits would
outweigh the overhead. E.g. saving and restoring an MSR across a VMX
roundtrip costs ~250 cycles, and if the guest diverged from the host
that cost would be paid on every run of the guest. In other words, if
there is a legitimate use case then it should be enabled by a new
per-VM capability.
Note, KVM still needs to emulate MSR_IA32_UMWAIT_CONTROL so that it can
correctly expose other WAITPKG features to the guest, e.g. TPAUSE,
UMWAIT and UMONITOR.
Fixes: 6e3ba4abce ("KVM: vmx: Emulate MSR IA32_UMWAIT_CONTROL")
Cc: stable@vger.kernel.org
Cc: Jingqi Liu <jingqi.liu@intel.com>
Cc: Tao Xu <tao3.xu@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200623005135.10414-1-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Explicitly pass the L2 GPA to kvm_arch_write_log_dirty(), which for all
intents and purposes is vmx_write_pml_buffer(), instead of having the
latter pull the GPA from vmcs.GUEST_PHYSICAL_ADDRESS. If the dirty bit
update is the result of KVM emulation (rare for L2), then the GPA in the
VMCS may be stale and/or hold a completely unrelated GPA.
Fixes: c5f983f6e8 ("nVMX: Implement emulated Page Modification Logging")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200622215832.22090-2-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The following race can cause lost map update events:
cpu1 cpu2
apic_map_dirty = true
------------------------------------------------------------
kvm_recalculate_apic_map:
pass check
mutex_lock(&kvm->arch.apic_map_lock);
if (!kvm->arch.apic_map_dirty)
and in process of updating map
-------------------------------------------------------------
other calls to
apic_map_dirty = true might be too late for affected cpu
-------------------------------------------------------------
apic_map_dirty = false
-------------------------------------------------------------
kvm_recalculate_apic_map:
bail out on
if (!kvm->arch.apic_map_dirty)
To fix it, record the beginning of an update of the APIC map in
apic_map_dirty. If another APIC map change switches apic_map_dirty
back to DIRTY during the update, kvm_recalculate_apic_map should not
make it CLEAN, and the other caller will go through the slow path.
Reported-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
1068ed4547 ("x86/msr: Lift AMD family 0x15 power-specific MSRs")
moved the three F15h power MSRs to the architectural list but that was
wrong as they belong in the family 0x15 list. That also caused:
In file included from trace/beauty/tracepoints/x86_msr.c:10:
perf/trace/beauty/generated/x86_arch_MSRs_array.c:292:45: error: initialized field overwritten [-Werror=override-init]
292 | [0xc0010280 - x86_AMD_V_KVM_MSRs_offset] = "F15H_PTSC",
| ^~~~~~~~~~~
perf/trace/beauty/generated/x86_arch_MSRs_array.c:292:45: note: (near initialization for 'x86_AMD_V_KVM_MSRs[640]')
due to MSR_F15H_PTSC ending up being defined twice. Move them where they
belong and drop the duplicate.
Also, drop the respective tools/ changes of the msr-index.h copy the
above commit added because perf tool developers prefer to go through
those changes themselves in order to figure out whether changes to the
kernel headers would need additional handling in perf.
Fixes: 1068ed4547 ("x86/msr: Lift AMD family 0x15 power-specific MSRs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lkml.kernel.org/r/20200621163323.14e8533f@canb.auug.org.au
Fix:
arch/x86/mm/init.c:503:21:
warning: no previous prototype for ‘init_memory_mapping’ [-Wmissing-prototypes]
unsigned long __ref init_memory_mapping(unsigned long start,
arch/x86/mm/init.c:745:13:
warning: no previous prototype for ‘poking_init’ [-Wmissing-prototypes]
void __init poking_init(void)
Lift init_memory_mapping() and poking_init() out of the ifdef
CONFIG_X86_64 to make the functions visible on 32-bit too.
Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200606123743.3277-1-b.thiel@posteo.de
The kernel needs to explicitly enable FSGSBASE. So, the application needs
to know if it can safely use these instructions. Just looking at the CPUID
bit is not enough because it may be running in a kernel that does not
enable the instructions.
One way for the application would be to just try and catch the SIGILL.
But that is difficult to do in libraries which may not want to overwrite
the signal handlers of the main application.
Enumerate the enabled FSGSBASE capability in bit 1 of AT_HWCAP2 in the ELF
aux vector. AT_HWCAP2 is already used by PPC for similar purposes.
The application can access it open coded or by using the getauxval()
function in newer versions of glibc.
[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1557309753-24073-18-git-send-email-chang.seok.bae@intel.com
Link: https://lkml.kernel.org/r/20200528201402.1708239-14-sashal@kernel.org
GSBASE is used to find per-CPU data in the kernel. But when GSBASE is
unknown, the per-CPU base can be found from the per_cpu_offset table with a
CPU NR. The CPU NR is extracted from the limit field of the CPUNODE entry
in GDT, or by the RDPID instruction. This is a prerequisite for using
FSGSBASE in the low level entry code.
Also, add the GAS-compatible RDPID macro as binutils 2.23 do not support
it. Support is added in version 2.27.
[ tglx: Massaged changelog ]
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1557309753-24073-12-git-send-email-chang.seok.bae@intel.com
Link: https://lkml.kernel.org/r/20200528201402.1708239-11-sashal@kernel.org
save_fsgs_for_kvm() is invoked via
vcpu_enter_guest()
kvm_x86_ops.prepare_guest_switch(vcpu)
vmx_prepare_switch_to_guest()
save_fsgs_for_kvm()
with preemption disabled, but interrupts enabled.
The upcoming FSGSBASE based GS safe needs interrupts to be disabled. This
could be done in the helper function, but that function is also called from
switch_to() which has interrupts disabled already.
Disable interrupts inside save_fsgs_for_kvm() and rename the function to
current_save_fsgs() so it can be invoked from other places.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200528201402.1708239-7-sashal@kernel.org
Add cpu feature conditional FSGSBASE access to the relevant helper
functions. That allows to accelerate certain FS/GS base operations in
subsequent changes.
Note, that while possible, the user space entry/exit GSBASE operations are
not going to use the new FSGSBASE instructions. The reason is that it would
require additional storage for the user space value which adds more
complexity to the low level code and experiments have shown marginal
benefit. This may be revisited later but for now the SWAPGS based handling
in the entry code is preserved except for the paranoid entry/exit code.
To preserve the SWAPGS entry mechanism introduce __[rd|wr]gsbase_inactive()
helpers. Note, for Xen PV, paravirt hooks can be added later as they might
allow a very efficient but different implementation.
[ tglx: Massaged changelog, convert it to noinstr and force inline
native_swapgs() ]
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1557309753-24073-7-git-send-email-chang.seok.bae@intel.com
Link: https://lkml.kernel.org/r/20200528201402.1708239-5-sashal@kernel.org
[ luto: Rename the variables from FS and GS to FSBASE and GSBASE and
make <asm/fsgsbase.h> safe to include on 32-bit kernels. ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/1557309753-24073-6-git-send-email-chang.seok.bae@intel.com
Link: https://lkml.kernel.org/r/20200528201402.1708239-4-sashal@kernel.org
The idle tasks created for each secondary CPU already have a random stack
canary generated by fork(). Copy the canary to the percpu variable before
starting the secondary CPU which removes the need to call
boot_init_stack_canary().
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200617225624.799335-1-brgerst@gmail.com
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
... into the global msr-index.h header because they're used in multiple
compilation units. Sort the MSR list a bit. Update the msr-index.h copy
in tools.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lkml.kernel.org/r/20200608164847.14232-1-bp@alien8.de
Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the case
where firmware doesn't initialize or save/restore across S3. This fixes
a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON
taking a #GP due to VMX not being fully enabled, i.e. breaks KVM.
Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already deals
with the case where the MSR is locked, and because APs already redo
init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow being
used to reinitialize APs upon wakeup. Do the call in the early wakeup
flow to avoid dependencies in the syscore_ops chain, e.g. simply adding
a resume hook is not guaranteed to work, as KVM does VMXON in its own
resume hook, kvm_resume(), when KVM has active guests.
Fixes: 21bd3467a5 ("KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR")
Reported-by: Brad Campbell <lists2009@fnarfbargle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Tested-by: Brad Campbell <lists2009@fnarfbargle.com>
Cc: stable@vger.kernel.org # v5.6
Link: https://lkml.kernel.org/r/20200608174134.11157-1-sean.j.christopherson@intel.com
Explain the rationale for annotating WARN(), even though, strictly
speaking printk() and friends are very much not safe in many of the
places we put them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Now that KCSAN relies on -tsan-distinguish-volatile we no longer need
the annotation for constant_test_bit(). Remove it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
The product mcnt * arch_max_freq_ratio can overflows u64.
For context, a large value for arch_max_freq_ratio would be 5000,
corresponding to a turbo_freq/base_freq ratio of 5 (normally it's more like
1500-2000). A large increment frequency for the MPERF counter would be 5GHz
(the base clock of all CPUs on the market today is less than that). With
these figures, a CPU would need to go without a scheduler tick for around 8
days for the u64 overflow to happen. It is unlikely, but the check is
warranted.
Under similar conditions, the difference acnt of two consecutive APERF
readings can overflow as well.
In these circumstances is appropriate to disable frequency invariant
accounting: the feature relies on measures of the clock frequency done at
every scheduler tick, which need to be "fresh" to be at all meaningful.
A note on i386: prior to version 5.1, the GCC compiler didn't have the
builtin function __builtin_mul_overflow. In these GCC versions the macro
check_mul_overflow needs __udivdi3() to do (u64)a/b, which the kernel
doesn't provide. For this reason this change fails to build on i386 if
GCC<5.1, and we protect the entire frequency invariant code behind
CONFIG_X86_64 (special thanks to "kbuild test robot" <lkp@intel.com>).
Fixes: 1567c3e346 ("x86, sched: Add support for frequency invariance")
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200531182453.15254-2-ggherdovich@suse.cz
People report that utime and stime from /proc/<pid>/stat become very
wrong when the numbers are big enough, especially if you watch these
counters incrementally.
Specifically, the current implementation of: stime*rtime/total,
results in a saw-tooth function on top of the desired line, where the
teeth grow in size the larger the values become. IOW, it has a
relative error.
The result is that, when watching incrementally as time progresses
(for large values), we'll see periods of pure stime or utime increase,
irrespective of the actual ratio we're striving for.
Replace scale_stime() with a math64.h helper: mul_u64_u64_div_u64()
that is far more accurate. This also allows architectures to override
the implementation -- for instance they can opt for the old algorithm
if this new one turns out to be too expensive for them.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200519172506.GA317395@hirez.programming.kicks-ass.net
Add perf text poke events for kprobes. That includes:
- the replaced instruction(s) which are executed out-of-line
i.e. arch_copy_kprobe() and arch_remove_kprobe()
- the INT3 that activates the kprobe
i.e. arch_arm_kprobe() and arch_disarm_kprobe()
- optimised kprobe function
i.e. arch_prepare_optimized_kprobe() and
__arch_remove_optimized_kprobe()
- optimised kprobe
i.e. arch_optimize_kprobes() and arch_unoptimize_kprobe()
Resulting in 8 possible text_poke events:
0: NULL -> probe.ainsn.insn (if ainsn.boostable && !kp.post_handler)
arch_copy_kprobe()
1: old0 -> INT3 arch_arm_kprobe()
// boosted kprobe active
2: NULL -> optprobe_trampoline arch_prepare_optimized_kprobe()
3: INT3,old1,old2,old3,old4 -> JMP32 arch_optimize_kprobes()
// optprobe active
4: JMP32 -> INT3,old1,old2,old3,old4
// optprobe disabled and kprobe active (this sometimes goes back to 3)
arch_unoptimize_kprobe()
5: optprobe_trampoline -> NULL arch_remove_optimized_kprobe()
// boosted kprobe active
6: INT3 -> old0 arch_disarm_kprobe()
7: probe.ainsn.insn -> NULL (if ainsn.boostable && !kp.post_handler)
arch_remove_kprobe()
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20200512121922.8997-6-adrian.hunter@intel.com
KVM now supports using interrupt for 'page ready' APF event delivery and
legacy mechanism was deprecated. Switch KVM guests to the new one.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-9-vkuznets@redhat.com>
[Use HYPERVISOR_CALLBACK_VECTOR instead of a separate vector. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Unmap a whole guest page if an MCE is encountered in it to avoid
follow-on MCEs leading to the guest crashing, by Tony Luck.
This change collided with the entry changes and the merge resolution
would have been rather unpleasant. To avoid that the entry branch was
merged in before applying this. The resulting code did not change
over the rebase.
* AMD MCE error thresholding machinery cleanup and hotplug sanitization, by
Thomas Gleixner.
* Change the MCE notifiers to denote whether they have handled the error
and not break the chain early by returning NOTIFY_STOP, thus giving the
opportunity for the later handlers in the chain to see it. By Tony Luck.
* Add AMD family 0x17, models 0x60-6f support, by Alexander Monakov.
* Last but not least, the usual round of fixes and improvements.
-----BEGIN PGP SIGNATURE-----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=iWiy
-----END PGP SIGNATURE-----
Merge tag 'ras-core-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RAS updates from Thomas Gleixner:
"RAS updates from Borislav Petkov:
- Unmap a whole guest page if an MCE is encountered in it to avoid
follow-on MCEs leading to the guest crashing, by Tony Luck.
This change collided with the entry changes and the merge
resolution would have been rather unpleasant. To avoid that the
entry branch was merged in before applying this. The resulting code
did not change over the rebase.
- AMD MCE error thresholding machinery cleanup and hotplug
sanitization, by Thomas Gleixner.
- Change the MCE notifiers to denote whether they have handled the
error and not break the chain early by returning NOTIFY_STOP, thus
giving the opportunity for the later handlers in the chain to see
it. By Tony Luck.
- Add AMD family 0x17, models 0x60-6f support, by Alexander Monakov.
- Last but not least, the usual round of fixes and improvements"
* tag 'ras-core-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
x86/mce/dev-mcelog: Fix -Wstringop-truncation warning about strncpy()
x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned
EDAC/amd64: Add AMD family 17h model 60h PCI IDs
hwmon: (k10temp) Add AMD family 17h model 60h PCI match
x86/amd_nb: Add AMD family 17h model 60h PCI IDs
x86/mcelog: Add compat_ioctl for 32-bit mcelog support
x86/mce: Drop bogus comment about mce.kflags
x86/mce: Fixup exception only for the correct MCEs
EDAC: Drop the EDAC report status checks
x86/mce: Add mce=print_all option
x86/mce: Change default MCE logger to check mce->kflags
x86/mce: Fix all mce notifiers to update the mce->kflags bitmask
x86/mce: Add a struct mce.kflags field
x86/mce: Convert the CEC to use the MCE notifier
x86/mce: Rename "first" function as "early"
x86/mce/amd, edac: Remove report_gart_errors
x86/mce/amd: Make threshold bank setting hotplug robust
x86/mce/amd: Cleanup threshold device remove path
x86/mce/amd: Straighten CPU hotplug path
x86/mce/amd: Sanitize thresholding device creation hotplug path
...
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-----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=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
...
- Loongson port
PPC:
- Fixes
ARM:
- Fixes
x86:
- KVM_SET_USER_MEMORY_REGION optimizations
- Fixes
- Selftest fixes
The guest side of the asynchronous page fault work has been delayed to 5.9
in order to sync with Thomas's interrupt entry rework.
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl7icj4UHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroPHGQgAj9+5j+f5v06iMP/+ponWwsVfh+5/
UR1gPbpMSFMKF0U+BCFxsBeGKWPDiz9QXaLfy6UGfOFYBI475Su5SoZ8/i/o6a2V
QjcKIJxBRNs66IG/774pIpONY8/mm/3b6vxmQktyBTqjb6XMGlOwoGZixj/RTp85
+uwSICxMlrijg+fhFMwC4Bo/8SFg+FeBVbwR07my88JaLj+3cV/NPolG900qLSa6
uPqJ289EQ86LrHIHXCEWRKYvwy77GFsmBYjKZH8yXpdzUlSGNexV8eIMAz50figu
wYRJGmHrRqwuzFwEGknv8SA3s2HVggXO4WVkWWCeJyO8nIVfYFUhME5l6Q==
=+Hh0
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Paolo Bonzini:
"The guest side of the asynchronous page fault work has been delayed to
5.9 in order to sync with Thomas's interrupt entry rework, but here's
the rest of the KVM updates for this merge window.
MIPS:
- Loongson port
PPC:
- Fixes
ARM:
- Fixes
x86:
- KVM_SET_USER_MEMORY_REGION optimizations
- Fixes
- Selftest fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (62 commits)
KVM: x86: do not pass poisoned hva to __kvm_set_memory_region
KVM: selftests: fix sync_with_host() in smm_test
KVM: async_pf: Inject 'page ready' event only if 'page not present' was previously injected
KVM: async_pf: Cleanup kvm_setup_async_pf()
kvm: i8254: remove redundant assignment to pointer s
KVM: x86: respect singlestep when emulating instruction
KVM: selftests: Don't probe KVM_CAP_HYPERV_ENLIGHTENED_VMCS when nested VMX is unsupported
KVM: selftests: do not substitute SVM/VMX check with KVM_CAP_NESTED_STATE check
KVM: nVMX: Consult only the "basic" exit reason when routing nested exit
KVM: arm64: Move hyp_symbol_addr() to kvm_asm.h
KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception
KVM: arm64: Make vcpu_cp1x() work on Big Endian hosts
KVM: arm64: Remove host_cpu_context member from vcpu structure
KVM: arm64: Stop sparse from moaning at __hyp_this_cpu_ptr
KVM: arm64: Handle PtrAuth traps early
KVM: x86: Unexport x86_fpu_cache and make it static
KVM: selftests: Ignore KVM 5-level paging support for VM_MODE_PXXV48_4K
KVM: arm64: Save the host's PtrAuth keys in non-preemptible context
KVM: arm64: Stop save/restoring ACTLR_EL1
KVM: arm64: Add emulation for 32bit guests accessing ACTLR2
...
For no reason other than beginning brainmelt, IDTENTRY_NMI was mapped to
IDTENTRY_IST.
This is not a problem on 64bit because the IST default entry point maps to
IDTENTRY_RAW which does not any entry handling. The surplus function
declaration for the noist C entry point is unused and as there is no ASM
code emitted for NMI this went unnoticed.
On 32bit IDTENTRY_IST maps to a regular IDTENTRY which does the normal
entry handling. That is clearly the wrong thing to do for NMI.
Map it to IDTENTRY_RAW to unbreak it. The IDTENTRY_NMI mapping needs to
stay to avoid emitting ASM code.
Fixes: 6271fef00b ("x86/entry: Convert NMI to IDTENTRY_NMI")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Debugged-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/CA+G9fYvF3cyrY+-iw_SZtpN-i2qA2BruHg4M=QYECU2-dNdsMw@mail.gmail.com
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
KCSAN is a dynamic race detector, which relies on compile-time
instrumentation, and uses a watchpoint-based sampling approach to detect
races.
The feature was under development for quite some time and has already found
legitimate bugs.
Unfortunately it comes with a limitation, which was only understood late in
the development cycle:
It requires an up to date CLANG-11 compiler
CLANG-11 is not yet released (scheduled for June), but it's the only
compiler today which handles the kernel requirements and especially the
annotations of functions to exclude them from KCSAN instrumentation
correctly.
These annotations really need to work so that low level entry code and
especially int3 text poke handling can be completely isolated.
A detailed discussion of the requirements and compiler issues can be found
here:
https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/
We came to the conclusion that trying to work around compiler limitations
and bugs again would end up in a major trainwreck, so requiring a working
compiler seemed to be the best choice.
For Continous Integration purposes the compiler restriction is manageable
and that's where most xxSAN reports come from.
For a change this limitation might make GCC people actually look at their
bugs. Some issues with CSAN in GCC are 7 years old and one has been 'fixed'
3 years ago with a half baken solution which 'solved' the reported issue
but not the underlying problem.
The KCSAN developers also ponder to use a GCC plugin to become independent,
but that's not something which will show up in a few days.
Blocking KCSAN until wide spread compiler support is available is not a
really good alternative because the continuous growth of lockless
optimizations in the kernel demands proper tooling support.
-----BEGIN PGP SIGNATURE-----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=iplm
-----END PGP SIGNATURE-----
Merge tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull the Kernel Concurrency Sanitizer from Thomas Gleixner:
"The Kernel Concurrency Sanitizer (KCSAN) is a dynamic race detector,
which relies on compile-time instrumentation, and uses a
watchpoint-based sampling approach to detect races.
The feature was under development for quite some time and has already
found legitimate bugs.
Unfortunately it comes with a limitation, which was only understood
late in the development cycle:
It requires an up to date CLANG-11 compiler
CLANG-11 is not yet released (scheduled for June), but it's the only
compiler today which handles the kernel requirements and especially
the annotations of functions to exclude them from KCSAN
instrumentation correctly.
These annotations really need to work so that low level entry code and
especially int3 text poke handling can be completely isolated.
A detailed discussion of the requirements and compiler issues can be
found here:
https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/
We came to the conclusion that trying to work around compiler
limitations and bugs again would end up in a major trainwreck, so
requiring a working compiler seemed to be the best choice.
For Continous Integration purposes the compiler restriction is
manageable and that's where most xxSAN reports come from.
For a change this limitation might make GCC people actually look at
their bugs. Some issues with CSAN in GCC are 7 years old and one has
been 'fixed' 3 years ago with a half baken solution which 'solved' the
reported issue but not the underlying problem.
The KCSAN developers also ponder to use a GCC plugin to become
independent, but that's not something which will show up in a few
days.
Blocking KCSAN until wide spread compiler support is available is not
a really good alternative because the continuous growth of lockless
optimizations in the kernel demands proper tooling support"
* tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
compiler_types.h, kasan: Use __SANITIZE_ADDRESS__ instead of CONFIG_KASAN to decide inlining
compiler.h: Move function attributes to compiler_types.h
compiler.h: Avoid nested statement expression in data_race()
compiler.h: Remove data_race() and unnecessary checks from {READ,WRITE}_ONCE()
kcsan: Update Documentation to change supported compilers
kcsan: Remove 'noinline' from __no_kcsan_or_inline
kcsan: Pass option tsan-instrument-read-before-write to Clang
kcsan: Support distinguishing volatile accesses
kcsan: Restrict supported compilers
kcsan: Avoid inserting __tsan_func_entry/exit if possible
ubsan, kcsan: Don't combine sanitizer with kcov on clang
objtool, kcsan: Add kcsan_disable_current() and kcsan_enable_current_nowarn()
kcsan: Add __kcsan_{enable,disable}_current() variants
checkpatch: Warn about data_race() without comment
kcsan: Use GFP_ATOMIC under spin lock
Improve KCSAN documentation a bit
kcsan: Make reporting aware of KCSAN tests
kcsan: Fix function matching in report
kcsan: Change data_race() to no longer require marking racing accesses
kcsan: Move kcsan_{disable,enable}_current() to kcsan-checks.h
...
1) Compilers uninline small atomic_* static inline functions which can
expose them to instrumentation.
2) The instrumentation of atomic primitives was done at the architecture
level while composites or fallbacks were provided at the generic level.
As a result there are no uninstrumented variants of the fallbacks.
Both issues were in the way of fully isolating fragile entry code pathes
and especially the text poke int3 handler which is prone to an endless
recursion problem when anything in that code path is about to be
instrumented. This was always a problem, but got elevated due to the new
batch mode updates of tracing.
The solution is to mark the functions __always_inline and to flip the
fallback and instrumentation so the non-instrumented variants are at the
architecture level and the instrumentation is done in generic code.
The latter introduces another fallback variant which will go away once all
architectures have been moved over to arch_atomic_*.
-----BEGIN PGP SIGNATURE-----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=Jkzv
-----END PGP SIGNATURE-----
Merge tag 'locking-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull atomics rework from Thomas Gleixner:
"Peter Zijlstras rework of atomics and fallbacks. This solves two
problems:
1) Compilers uninline small atomic_* static inline functions which
can expose them to instrumentation.
2) The instrumentation of atomic primitives was done at the
architecture level while composites or fallbacks were provided at
the generic level. As a result there are no uninstrumented
variants of the fallbacks.
Both issues were in the way of fully isolating fragile entry code
pathes and especially the text poke int3 handler which is prone to an
endless recursion problem when anything in that code path is about to
be instrumented. This was always a problem, but got elevated due to
the new batch mode updates of tracing.
The solution is to mark the functions __always_inline and to flip the
fallback and instrumentation so the non-instrumented variants are at
the architecture level and the instrumentation is done in generic
code.
The latter introduces another fallback variant which will go away once
all architectures have been moved over to arch_atomic_*"
* tag 'locking-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomics: Flip fallbacks and instrumentation
asm-generic/atomic: Use __always_inline for fallback wrappers
- Unbreak paravirt VDSO clocks. While the VDSO code was moved into lib
for sharing a subtle check for the validity of paravirt clocks got
replaced. While the replacement works perfectly fine for bare metal as
the update of the VDSO clock mode is synchronous, it fails for paravirt
clocks because the hypervisor can invalidate them asynchronous. Bring
it back as an optional function so it does not inflict this on
architectures which are free of PV damage.
- Fix the jiffies to jiffies64 mapping on 64bit so it does not trigger
an ODR violation on newer compilers
- Three fixes for the SSBD and *IB* speculation mitigation maze to ensure
consistency, not disabling of some *IB* variants wrongly and to prevent
a rogue cross process shutdown of SSBD. All marked for stable.
- Add yet more CPU models to the splitlock detection capable list !@#%$!
- Bring the pr_info() back which tells that TSC deadline timer is enabled.
- Reboot quirk for MacBook6,1
-----BEGIN PGP SIGNATURE-----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=VlBk
-----END PGP SIGNATURE-----
Merge tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more x86 updates from Thomas Gleixner:
"A set of fixes and updates for x86:
- Unbreak paravirt VDSO clocks.
While the VDSO code was moved into lib for sharing a subtle check
for the validity of paravirt clocks got replaced. While the
replacement works perfectly fine for bare metal as the update of
the VDSO clock mode is synchronous, it fails for paravirt clocks
because the hypervisor can invalidate them asynchronously.
Bring it back as an optional function so it does not inflict this
on architectures which are free of PV damage.
- Fix the jiffies to jiffies64 mapping on 64bit so it does not
trigger an ODR violation on newer compilers
- Three fixes for the SSBD and *IB* speculation mitigation maze to
ensure consistency, not disabling of some *IB* variants wrongly and
to prevent a rogue cross process shutdown of SSBD. All marked for
stable.
- Add yet more CPU models to the splitlock detection capable list
!@#%$!
- Bring the pr_info() back which tells that TSC deadline timer is
enabled.
- Reboot quirk for MacBook6,1"
* tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vdso: Unbreak paravirt VDSO clocks
lib/vdso: Provide sanity check for cycles (again)
clocksource: Remove obsolete ifdef
x86_64: Fix jiffies ODR violation
x86/speculation: PR_SPEC_FORCE_DISABLE enforcement for indirect branches.
x86/speculation: Prevent rogue cross-process SSBD shutdown
x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.
x86/cpu: Add Sapphire Rapids CPU model number
x86/split_lock: Add Icelake microserver and Tigerlake CPU models
x86/apic: Make TSC deadline timer detection message visible
x86/reboot/quirks: Add MacBook6,1 reboot quirk
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>
'Page not present' event may or may not get injected depending on
guest's state. If the event wasn't injected, there is no need to
inject the corresponding 'page ready' event as the guest may get
confused. E.g. Linux thinks that the corresponding 'page not present'
event wasn't delivered *yet* and allocates a 'dummy entry' for it.
This entry is never freed.
Note, 'wakeup all' events have no corresponding 'page not present'
event and always get injected.
s390 seems to always be able to inject 'page not present', the
change is effectively a nop.
Suggested-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200610175532.779793-2-vkuznets@redhat.com>
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=208081
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
An interesting thing happened when a guest Linux instance took a machine
check. The VMM unmapped the bad page from guest physical space and
passed the machine check to the guest.
Linux took all the normal actions to offline the page from the process
that was using it. But then guest Linux crashed because it said there
was a second machine check inside the kernel with this stack trace:
do_memory_failure
set_mce_nospec
set_memory_uc
_set_memory_uc
change_page_attr_set_clr
cpa_flush
clflush_cache_range_opt
This was odd, because a CLFLUSH instruction shouldn't raise a machine
check (it isn't consuming the data). Further investigation showed that
the VMM had passed in another machine check because is appeared that the
guest was accessing the bad page.
Fix is to check the scope of the poison by checking the MCi_MISC register.
If the entire page is affected, then unmap the page. If only part of the
page is affected, then mark the page as uncacheable.
This assumes that VMMs will do the logical thing and pass in the "whole
page scope" via the MCi_MISC register (since they unmapped the entire
page).
[ bp: Adjust to x86/entry changes. ]
Fixes: 284ce4011b ("x86/memory_failure: Introduce {set, clear}_mce_nospec()")
Reported-by: Jue Wang <juew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jue Wang <juew@google.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200520163546.GA7977@agluck-desk2.amr.corp.intel.com
to fixup conflicts in arch/x86/kernel/cpu/mce/core.c so MCE specific follow
up patches can be applied without creating a horrible merge conflict
afterwards.
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>
- 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
Because:
irq_enter_rcu() includes lockdep_hardirq_enter()
irq_exit_rcu() does *NOT* include lockdep_hardirq_exit()
Which resulted in two 'stray' lockdep_hardirq_exit() calls in
idtentry.h, and me spending a long time trying to find the matching
enter calls.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.359433429@infradead.org
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
Because DRn access is 'difficult' with virt; but the DR7 read is cheaper
than a cacheline miss on native, add a virt specific fast path to
local_db_save(), such that when breakpoints are not in use to avoid
touching DRn entirely.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.187833200@infradead.org
In order to allow other exceptions than #DB to disable breakpoints,
provide common helpers.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.012060983@infradead.org
Remove all the code which was there to emit the system vector stubs. All
users are gone.
Move the now unused GET_CR2_INTO macro muck to head_64.S where the last
user is. Fixup the eye hurting comment there while at it.
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/20200521202119.927433002@linutronix.de
The scheduler IPI does not need the full interrupt entry handling logic
when the entry is from kernel mode. Use IDTENTRY_SYSVEC_SIMPLE and spare
all the overhead.
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/20200521202119.835425642@linutronix.de
Convert the last oldstyle defined vector to IDTENTRY_SYSVEC:
- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64-bit
- Remove the BUILD_INTERRUPT entries in 32-bit
- Remove the old prototypes
Fixup the related XEN code by providing the primary C entry point in x86 to
avoid cluttering the generic code with X86'isms.
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/20200521202119.741950104@linutronix.de
Convert various hypervisor vectors to IDTENTRY_SYSVEC:
- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64-bit
- Remove the BUILD_INTERRUPT entries in 32-bit
- 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>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20200521202119.647997594@linutronix.de
Convert KVM specific system vectors to IDTENTRY_SYSVEC*:
The two empty stub handlers which only increment the stats counter do no
need to run on the interrupt stack. Use IDTENTRY_SYSVEC_SIMPLE for them.
The wakeup handler does more work and runs on the interrupt stack.
None of these handlers need to save and restore the irq_regs pointer.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202119.555715519@linutronix.de
Convert various system vectors to IDTENTRY_SYSVEC:
- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64-bit
- Remove the BUILD_INTERRUPT entries in 32-bit
- 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/20200521202119.464812973@linutronix.de
Convert SMP system vectors to IDTENTRY_SYSVEC:
- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64-bit
- Remove the BUILD_INTERRUPT entries in 32-bit
- 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/20200521202119.372234635@linutronix.de
Convert APIC interrupts to IDTENTRY_SYSVEC:
- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64-bit
- Remove the BUILD_INTERRUPT entries in 32-bit
- 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/20200521202119.280728850@linutronix.de
Provide IDTENTRY variants for system vectors to consolidate the different
mechanisms to emit the ASM stubs for 32- and 64-bit.
On 64-bit this also moves the stack switching from ASM to C code. 32-bit will
excute the system vectors w/o stack switching as before.
The simple variant is meant for "empty" system vectors like scheduler IPI
and KVM posted interrupt vectors. These do not need the full glory of irq
enter/exit handling with softirq processing and more.
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/20200521202119.185317067@linutronix.de
Replace the extra interrupt handling code and reuse the existing idtentry
machinery. This moves the irq stack switching on 64-bit from ASM to C code;
32-bit already does the stack switching in C.
This requires to remove HAVE_IRQ_EXIT_ON_IRQ_STACK as the stack switch is
not longer in the low level entry code.
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/20200521202119.078690991@linutronix.de
Provide a seperate IDTENTRY macro for device interrupts. Similar to
IDTENTRY_ERRORCODE with the addition of invoking irq_enter/exit_rcu() and
providing the errorcode as a 'u8' argument to the C function, which
truncates the sign extended vector number.
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/20200521202118.984573165@linutronix.de
To consolidate the interrupt entry/exit code vs. the other exceptions
make handle_irq() an inline and handle both 64-bit and 32-bit mode.
Preparatory change to move irq stack switching for 64-bit to C which allows
to consolidate the entry exit handling by reusing the idtentry machinery
both in ASM and C.
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/20200521202118.889972748@linutronix.de
Device interrupts which go through do_IRQ() or the spurious interrupt
handler have their separate entry code on 64 bit for no good reason.
Both 32 and 64 bit transport the vector number through ORIG_[RE]AX in
pt_regs. Further the vector number is forced to fit into an u8 and is
complemented and offset by 0x80 so it's in the signed character
range. Otherwise GAS would expand the pushq to a 5 byte instruction for any
vector > 0x7F.
Treat the vector number like an error code and hand it to the C function as
argument. This allows to get rid of the extra entry code in a later step.
Simplify the error code push magic by implementing the pushq imm8 via a
'.byte 0x6a, vector' sequence so GAS is not able to screw it up. As the
pushq imm8 is sign extending the resulting error code needs to be truncated
to 8 bits in C code.
Originally-by: Andy Lutomirski <luto@kernel.org>
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/20200521202118.796915981@linutronix.de
The only difference is the name of the per-CPU variable: irq_regs
vs. __irq_regs, but the accessor functions are identical.
Remove the pointless copy and use the generic variant.
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/20200521202118.704169051@linutronix.de
Now that all exceptions are converted over the sane flag is not longer
needed. Also the vector argument of idtentry_body on 64-bit is pointless
now.
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/20200521202118.331115895@linutronix.de
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
Convert the XEN/PV hypercall to IDTENTRY:
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64-bit
- Remove the open coded ASM entry code in 32-bit
- Remove the old prototypes
The handler stubs need to stay in ASM code as they need corner case handling
and adjustment of the stack pointer.
Provide a new C function which invokes the entry/exit handling and calls
into the XEN handler on the interrupt stack if required.
The exit code is slightly different from the regular idtentry_exit() on
non-preemptible kernels. If the hypercall is preemptible and need_resched()
is set then XEN provides a preempt hypercall scheduling function.
Move this functionality into the entry code so it can use the existing
idtentry functionality.
[ mingo: Build fixes. ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200521202118.055270078@linutronix.de
Device interrupt handlers and system vector handlers are executed on the
interrupt stack. The stack switch happens in the low level assembly entry
code. This conflicts with the efforts to consolidate the exit code in C to
ensure correctness vs. RCU and tracing.
As there is no way to move #DB away from IST due to the MOV SS issue, the
requirements vs. #DB and NMI for switching to the interrupt stack do not
exist anymore. The only requirement is that interrupts are disabled.
That allows the moving of the stack switching to C code, which simplifies the
entry/exit handling further, because it allows the switching of stacks after
handling the entry and on exit before handling RCU, returning to usermode and
kernel preemption in the same way as for regular exceptions.
The initial attempt of having the stack switching in inline ASM caused too
much headache vs. objtool and the unwinder. After analysing the use cases
it was agreed on that having the stack switch in ASM for the price of an
indirect call is acceptable, as the main users are indirect call heavy
anyway and the few system vectors which are empty shells (scheduler IPI and
KVM posted interrupt vectors) can run from the regular stack.
Provide helper functions to check whether the interrupt stack is already
active and whether stack switching is required.
64-bit only for now, as 32-bit has a variant of that already. Once this is
cleaned up, the two implementations might be consolidated as an additional
cleanup on top.
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/20200521202117.763775313@linutronix.de
Now that everything is converted to conditional RCU handling remove
idtentry_enter/exit() and tidy up the conditional functions.
This does not remove rcu_irq_exit_preempt(), to avoid conflicts with the RCU
tree. Will be removed once all of this hits Linus's tree.
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/20200521202117.473597954@linutronix.de
Switch all idtentry_enter/exit() users over to the new conditional RCU
handling scheme and make the user mode entries in #DB, #INT3 and #MCE use
the user mode idtentry functions.
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/20200521202117.382387286@linutronix.de
As there are exceptions which already handle entry from user mode and from
kernel mode separately, providing explicit user entry/exit handling callbacks
makes sense and makes the code easier to understand.
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/20200521202117.289548561@linutronix.de
After a lengthy discussion [1] it turned out that RCU does not need a full
rcu_irq_enter/exit() when RCU is already watching. All it needs if
NOHZ_FULL is active is to check whether the tick needs to be restarted.
This allows to avoid a separate variant for the pagefault handler which
cannot invoke rcu_irq_enter() on a kernel pagefault which might sleep.
The cond_rcu argument is only temporary and will be removed once the
existing users of idtentry_enter/exit() have been cleaned up. After that
the code can be significantly simplified.
[ mingo: Simplified the control flow ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Paul E. McKenney" <paulmck@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: [1] https://lkml.kernel.org/r/20200515235125.628629605@linutronix.de
Link: https://lore.kernel.org/r/20200521202117.181397835@linutronix.de
Convert #DF to IDTENTRY_DF
- Implement the C entry point with DEFINE_IDTENTRY_DF
- Emit the ASM stub with DECLARE_IDTENTRY_DF on 64bit
- Remove the ASM idtentry in 64bit
- Adjust the 32bit shim code
- Fixup the XEN/PV code
- 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: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135315.583415264@linutronix.de
Provide a separate macro for #DF as this needs to emit paranoid only code
and has also a special ASM stub in 32bit.
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/20200505135315.583415264@linutronix.de
Provide NOIST entry point macros which allows to implement NOIST variants
of the C entry points. These are invoked when #DB or #MC enter from user
space. This allows explicit handling of the difference between user mode
and kernel mode entry later.
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/20200505135315.084882104@linutronix.de
Convert #DB to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY_DB
- 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
- 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: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.900297476@linutronix.de
Mark all functions in the fragile code parts noinstr or force inlining so
they can't be instrumented.
Also make the hardware latency tracer invocation explicit outside of
non-instrumentable section.
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/20200505135314.716186134@linutronix.de
Convert #NMI to IDTENTRY_NMI:
- Implement the C entry point with DEFINE_IDTENTRY_NMI
- Fixup the XEN/PV code
- 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: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.609932306@linutronix.de
XEN/PV has special wrappers for NMI and DB exceptions. They redirect these
exceptions through regular IDTENTRY points. Provide the necessary IDTENTRY
macros to make this work
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/20200505135314.518622698@linutronix.de
Convert #MC to IDTENTRY_MCE:
- Implement the C entry points with DEFINE_IDTENTRY_MCE
- Emit the ASM stub with DECLARE_IDTENTRY_MCE
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the error code from *machine_check_vector() as
it is always 0 and not used by any of the functions
it can point to. Fixup all the functions as well.
No functional change.
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/20200505135314.334980426@linutronix.de
Same as IDTENTRY but for exceptions which run on Interrupt Stacks (IST) on
64bit. For 32bit this maps to IDTENTRY.
There are 3 variants which will be used:
IDTENTRY_MCE
IDTENTRY_DB
IDTENTRY_NMI
These map to IDTENTRY_IST, but only the MCE and DB variants are emitting
ASM code as the NMI entry needs hand crafted ASM still.
The function defines do not contain any idtenter/exit calls as these
exceptions need special treatment.
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/20200505135314.137125609@linutronix.de
Convert #BP to IDTENTRY_RAW:
- Implement the C entry point with DEFINE_IDTENTRY_RAW
- Invoke idtentry_enter/exit() from the function body
- Emit the ASM stub with DECLARE_IDTENTRY_RAW
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
No functional change.
This could be a plain IDTENTRY, but as Peter pointed out INT3 is broken
vs. the static key in the context tracking code as this static key might be
in the state of being patched and has an int3 which would recurse forever.
IDTENTRY_RAW is therefore chosen to allow addressing this issue without
lots of code churn.
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/20200505135313.938474960@linutronix.de
Some exception handlers need to do extra work before any of the entry
helpers are invoked. Provide IDTENTRY_RAW for this.
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/20200505135313.830540017@linutronix.de
In order to ensure poke_int3_handler() is completely self contained -- this
is called while modifying other text, imagine the fun of hitting another
INT3 -- ensure that everything it uses is not traced.
The primary means here is to force inlining; bsearch() is notrace because
all of lib/ is.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135313.410702173@linutronix.de
Convert the IRET exception handler to IDTENTRY_SW. This is slightly
different than the conversions of hardware exceptions as the IRET exception
is invoked via an exception table when IRET faults. So it just uses the
IDTENTRY_SW mechanism for consistency. It does not emit ASM code as it does
not fit the other idtentry exceptions.
- Implement the C entry point with DEFINE_IDTENTRY_SW() which maps to
DEFINE_IDTENTRY()
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134906.128769226@linutronix.de
Convert #XF to IDTENTRY_ERRORCODE:
- Implement the C entry point with DEFINE_IDTENTRY
- Emit the ASM stub with DECLARE_IDTENTRY
- Handle INVD_BUG in C
- Remove the ASM idtentry in 64bit
- Remove the open coded ASM entry code in 32bit
- Fixup the XEN/PV code
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134906.021552202@linutronix.de
Convert #AC to IDTENTRY_ERRORCODE:
- 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
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134905.928967113@linutronix.de
Convert #MF to IDTENTRY_ERRORCODE:
- 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
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134905.838823510@linutronix.de
Convert #SPURIOUS to IDTENTRY_ERRORCODE:
- 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
- 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: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.728077036@linutronix.de
Convert #GP to IDTENTRY_ERRORCODE:
- 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
- Remove the old prototypes
- Remove the RCU warning as the new entry macro ensures correctness
No functional change.
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/20200505134905.637269946@linutronix.de
Linus Torvalds
Andy Lutomirski
Andy Shevchenko
steve.wahl@hpe.com
Sedat Dilek
Jian Cai
Uros Bizjak
Thomas Gleixner
Mohammed Gamal
Paolo Bonzini
Peter Zijlstra
Sean Christopherson
Xiaoyao Li
Krish Sadhukhan
Zhenzhong Duan
Jim Mattson
Kan Liang
Ingo Molnar
Like Xu
Srinivas Pandruvada
Joerg Roedel
Petteri Aimonen
Mauro Carvalho Chehab
Christoph Hellwig
Al Viro
Borislav Petkov
Benjamin Thiel
Andi Kleen
Chang S. Bae
Brian Gerst
Giovanni Gherdovich
Oleg Nesterov
Adrian Hunter
Vitaly Kuznetsov
Tony Luck