Граф коммитов

616330 Коммитов

Автор SHA1 Сообщение Дата
James Hogan 8985d50382 MIPS: KVM: Add missing gfn range check
kvm_mips_handle_mapped_seg_tlb_fault() calculates the guest frame number
based on the guest TLB EntryLo values, however it is not range checked
to ensure it lies within the guest_pmap. If the physical memory the
guest refers to is out of range then dump the guest TLB and emit an
internal error.

Fixes: 858dd5d457 ("KVM/MIPS32: MMU/TLB operations for the Guest.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:28 +02:00
James Hogan c604cffa93 MIPS: KVM: Fix mapped fault broken commpage handling
kvm_mips_handle_mapped_seg_tlb_fault() appears to map the guest page at
virtual address 0 to PFN 0 if the guest has created its own mapping
there. The intention is unclear, but it may have been an attempt to
protect the zero page from being mapped to anything but the comm page in
code paths you wouldn't expect from genuine commpage accesses (guest
kernel mode cache instructions on that address, hitting trapping
instructions when executing from that address with a coincidental TLB
eviction during the KVM handling, and guest user mode accesses to that
address).

Fix this to check for mappings exactly at KVM_GUEST_COMMPAGE_ADDR (it
may not be at address 0 since commit 42aa12e74e ("MIPS: KVM: Move
commpage so 0x0 is unmapped")), and set the corresponding EntryLo to be
interpreted as 0 (invalid).

Fixes: 858dd5d457 ("KVM/MIPS32: MMU/TLB operations for the Guest.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:28 +02:00
Christoffer Dall a28ebea2ad KVM: Protect device ops->create and list_add with kvm->lock
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.

Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.

The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:27 +02:00
Christoffer Dall 023e9fddc3 KVM: PPC: Move xics_debugfs_init out of create
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.

Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-08-12 12:01:26 +02:00
Julius Niedworok aca411a4b1 KVM: s390: reset KVM_REQ_MMU_RELOAD if mapping the prefix failed
When triggering KVM_RUN without a user memory region being mapped
(KVM_SET_USER_MEMORY_REGION) a validity intercept occurs. This could
happen, if the user memory region was not mapped initially or if it
was unmapped after the vcpu is initialized. The function
kvm_s390_handle_requests checks for the KVM_REQ_MMU_RELOAD bit. The
check function always clears this bit. If gmap_mprotect_notify
returns an error code, the mapping failed, but the KVM_REQ_MMU_RELOAD
was not set anymore. So the next time kvm_s390_handle_requests is
called, the execution would fall trough the check for
KVM_REQ_MMU_RELOAD. The bit needs to be resetted, if
gmap_mprotect_notify returns an error code. Resetting the bit with
kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu) fixes the bug.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Julius Niedworok <jniedwor@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-08-12 09:11:08 +02:00
Julius Niedworok 75a4615c95 KVM: s390: set the prefix initially properly
When KVM_RUN is triggered on a VCPU without an initial reset, a
validity intercept occurs.
Setting the prefix will set the KVM_REQ_MMU_RELOAD bit initially,
thus preventing the bug.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Julius Niedworok <jniedwor@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-08-12 09:10:17 +02:00
Kan Liang 95f3be7984 perf/x86/intel/uncore: Add enable_box for client MSR uncore
There are bug reports about miscounting uncore counters on some
client machines like Sandybridge, Broadwell and Skylake. It is
very likely to be observed on idle systems.

This issue is caused by a hardware issue. PERF_GLOBAL_CTL could be
cleared after Package C7, and nothing will be count.
The related errata (HSD 158) could be found in:

  www.intel.com/content/dam/www/public/us/en/documents/specification-updates/4th-gen-core-family-desktop-specification-update.pdf

This patch tries to work around this issue by re-enabling PERF_GLOBAL_CTL
in ->enable_box(). The workaround does not cover all cases. It helps for new
events after returning from C7. But it cannot prevent C7, it will still
miscount if a counter is already active.

There is no drawback in leaving it enabled, so it does not need
disable_box() here.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1470925874-59943-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-12 08:35:05 +02:00
Kan Liang 10e9e7bd59 perf/x86/intel/uncore: Fix uncore num_counters
Some uncore boxes' num_counters value for Haswell server and
Broadwell server are not correct (too large, off by one).

This issue was found by comparing the code with the document. Although
there is no bug report from users yet, accessing non-existent counters
is dangerous and the behavior is undefined: it may cause miscounting or
even crashes.

This patch makes them consistent with the uncore document.

Reported-by: Lukasz Odzioba <lukasz.odzioba@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1470925820-59847-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-12 08:35:04 +02:00
Denys Vlasenko 68187872c7 uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions
Since instruction decoder now supports EVEX-encoded instructions, two fixes
are needed to correctly handle them in uprobes.

Extended bits for MODRM.rm field need to be sanitized just like we do it
for VEX3, to avoid encoding wrong register for register-relative access.

EVEX has _two_ extended bits: b and x. Theoretically, EVEX.x should be
ignored by the CPU (since GPRs go only up to 15, not 31), but let's be
paranoid here: proper encoding for register-relative access
should have EVEX.x = 1.

Secondly, we should fetch vex.vvvv for EVEX too.
This is now super easy because instruction decoder populates
vex_prefix.bytes[2] for all flavors of (e)vex encodings, even for VEX2.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # v4.1+
Fixes: 8a764a875f ("x86/asm/decoder: Create artificial 3rd byte for 2-byte VEX")
Link: http://lkml.kernel.org/r/20160811154521.20469-1-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-12 08:29:24 +02:00
Linus Torvalds 4b9eaf33d8 Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "7 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/memory_hotplug.c: initialize per_cpu_nodestats for hotadded pgdats
  mm, oom: fix uninitialized ret in task_will_free_mem()
  kasan: remove the unnecessary WARN_ONCE from quarantine.c
  mm: memcontrol: fix memcg id ref counter on swap charge move
  mm: memcontrol: fix swap counter leak on swapout from offline cgroup
  proc, meminfo: use correct helpers for calculating LRU sizes in meminfo
  mm/hugetlb: fix incorrect hugepages count during mem hotplug
2016-08-11 16:58:24 -07:00
Reza Arbab 5830169f47 mm/memory_hotplug.c: initialize per_cpu_nodestats for hotadded pgdats
The following oops occurs after a pgdat is hotadded:

  Unable to handle kernel paging request for data at address 0x00c30001
  Faulting instruction address: 0xc00000000022f8f4
  Oops: Kernel access of bad area, sig: 11 [#1]
  SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in: ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter nls_utf8 isofs sg virtio_balloon uio_pdrv_genirq uio ip_tables xfs libcrc32c sr_mod cdrom sd_mod virtio_net ibmvscsi scsi_transport_srp virtio_pci virtio_ring virtio dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W 4.8.0-rc1-device #110
  task: c000000000ef3080 task.stack: c000000000f6c000
  NIP: c00000000022f8f4 LR: c00000000022f948 CTR: 0000000000000000
  REGS: c000000000f6fa50 TRAP: 0300   Tainted: G        W (4.8.0-rc1-device)
  MSR: 800000010280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]>  CR: 84002028  XER: 20000000
  CFAR: d000000001d2013c DAR: 0000000000c30001 DSISR: 40000000 SOFTE: 0
  NIP refresh_cpu_vm_stats+0x1a4/0x2f0
  LR refresh_cpu_vm_stats+0x1f8/0x2f0
  Call Trace:
    refresh_cpu_vm_stats+0x1f8/0x2f0 (unreliable)

Add per_cpu_nodestats initialization to the hotplug codepath.

Link: http://lkml.kernel.org/r/1470931473-7090-1-git-send-email-arbab@linux.vnet.ibm.com
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:14 -07:00
Geert Uytterhoeven f33e6f0671 mm, oom: fix uninitialized ret in task_will_free_mem()
mm/oom_kill.c: In function `task_will_free_mem':
    mm/oom_kill.c:767: warning: `ret' may be used uninitialized in this function

If __task_will_free_mem() is never called inside the for_each_process()
loop, ret will not be initialized.

Fixes: 1af8bb4326 ("mm, oom: fortify task_will_free_mem()")
Link: http://lkml.kernel.org/r/1470255599-24841-1-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:14 -07:00
Alexander Potapenko bcbf0d566b kasan: remove the unnecessary WARN_ONCE from quarantine.c
It's quite unlikely that the user will so little memory that the per-CPU
quarantines won't fit into the given fraction of the available memory.
Even in that case he won't be able to do anything with the information
given in the warning.

Link: http://lkml.kernel.org/r/1470929182-101413-1-git-send-email-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kuthonuzo Luruo <kuthonuzo.luruo@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:14 -07:00
Vladimir Davydov 615d66c37c mm: memcontrol: fix memcg id ref counter on swap charge move
Since commit 73f576c04b ("mm: memcontrol: fix cgroup creation failure
after many small jobs") swap entries do not pin memcg->css.refcnt
directly.  Instead, they pin memcg->id.ref.  So we should adjust the
reference counters accordingly when moving swap charges between cgroups.

Fixes: 73f576c04b ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Link: http://lkml.kernel.org/r/9ce297c64954a42dc90b543bc76106c4a94f07e8.1470219853.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>	[3.19+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:13 -07:00
Vladimir Davydov 1f47b61fb4 mm: memcontrol: fix swap counter leak on swapout from offline cgroup
An offline memory cgroup might have anonymous memory or shmem left
charged to it and no swap.  Since only swap entries pin the id of an
offline cgroup, such a cgroup will have no id and so an attempt to
swapout its anon/shmem will not store memory cgroup info in the swap
cgroup map.  As a result, memcg->swap or memcg->memsw will never get
uncharged from it and any of its ascendants.

Fix this by always charging swapout to the first ancestor cgroup that
hasn't released its id yet.

[hannes@cmpxchg.org: add comment to mem_cgroup_swapout]
[vdavydov@virtuozzo.com: use WARN_ON_ONCE() in mem_cgroup_id_get_online()]
  Link: http://lkml.kernel.org/r/20160803123445.GJ13263@esperanza
Fixes: 73f576c04b ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Link: http://lkml.kernel.org/r/5336daa5c9a32e776067773d9da655d2dc126491.1470219853.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>	[3.19+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:13 -07:00
Mel Gorman 2f95ff90b9 proc, meminfo: use correct helpers for calculating LRU sizes in meminfo
meminfo_proc_show() and si_mem_available() are using the wrong helpers
for calculating the size of the LRUs.  The user-visible impact is that
there appears to be an abnormally high number of unevictable pages.

Link: http://lkml.kernel.org/r/20160805105805.GR2799@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:13 -07:00
zhong jiang c1470b33bb mm/hugetlb: fix incorrect hugepages count during mem hotplug
When memory hotplug operates, free hugepages will be freed if the
movable node is offline.  Therefore, /proc/sys/vm/nr_hugepages will be
incorrect.

Fix it by reducing max_huge_pages when the node is offlined.

n-horiguchi@ah.jp.nec.com said:

: dissolve_free_huge_page intends to break a hugepage into buddy, and the
: destination hugepage is supposed to be allocated from the pool of the
: destination node, so the system-wide pool size is reduced.  So adding
: h->max_huge_pages-- makes sense to me.

Link: http://lkml.kernel.org/r/1470624546-902-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-11 16:58:13 -07:00
Linus Torvalds d3396e1e4e ARM: SoC fixes
A couple of bug fixes have come in for v4.8 so far. Since the first few were
 originally meant to go into -rc1 (but didn't get sent in time for travel
 reasons), the branch is unfortunately based on top of a commit in the
 middle of the merge window rather than -rc1.
 
 Content-wise we have
 
 - A fix for the last remaining broken build in kernelci,
   getting mach-shmobile to build again with SMP disabled
 - A fix for a realview regression that broke real hardware but
   not the qemu model that everyone uses in practice (needed
   for v4.7 as well)
 - A merge conflict fix for Tegra that also broke v4.7
 - Two Kconfig fixes for arm64 build regressions
 - A couple of arm32 build warning fixes (all harmless)
 - Fixing the RTC on Exynos7 Espresso (which apparently
   never worked right)
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Arnd Bergmann:
 "A couple of bug fixes have come in for v4.8 so far.  Since the first
  few were originally meant to go into -rc1 (but didn't get sent in time
  for travel reasons), the branch is unfortunately based on top of a
  commit in the middle of the merge window rather than -rc1.

  Content-wise we have:

   - a fix for the last remaining broken build in kernelci, getting
     mach-shmobile to build again with SMP disabled

   - a fix for a realview regression that broke real hardware but not
     the qemu model that everyone uses in practice (needed for v4.7 as
     well)

   - a merge conflict fix for Tegra that also broke v4.7

   - two Kconfig fixes for arm64 build regressions

   - a couple of arm32 build warning fixes (all harmless)

   - fix the RTC on Exynos7 Espresso (which apparently never worked
     right)"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  Merge tag 'pxa-fixes-v4.8' of https://github.com/rjarzmik/linux into randconfig-4.8
  arm64: Kconfig: select HISILICON_IRQ_MBIGEN only if PCI is selected
  arm64: Kconfig: select ALPINE_MSI only if PCI is selected
  ARM: dts: realview: Fix PBX-A9 cache description
  ARM: tegra: fix erroneous address in dts
  ARM: dts: add syscon compatible string for AP syscon
  ARM: dts: add syscon compatible string for CP syscon
  ARM: oxnas: select reset controller framework
  ARM: hide mach-*/ include for ARM_SINGLE_ARMV7M
  ARM: don't include removed directories
  Revert "ARM: aspeed: adapt defconfigs for new CONFIG_PRINTK_TIME"
  ARM: shmobile: don't call platform_can_secondary_boot on UP
  MAINTAINER: alpine: add a mailing list
  ARM: do away with final ARCH_REQUIRE_GPIOLIB
  arm64: dts: Fix RTC by providing rtc_src clock
2016-08-11 14:14:23 -07:00
Linus Torvalds 6da7e95326 virtio/vhost: fixes and cleanups for 4.8
- Misc fixes and cleanups all over the place.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost fixes and cleanups from Michael Tsirkin:
 "Misc fixes and cleanups all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio/s390: deprecate old transport
  virtio/s390: keep early_put_chars
  virtio_blk: Fix a slient kernel panic
  virtio-vsock: fix include guard typo
  vhost/vsock: fix vhost virtio_vsock_pkt use-after-free
  9p/trans_virtio: use kvfree() for iov_iter_get_pages_alloc()
  virtio: fix error handling for debug builds
  virtio: fix memory leak in virtqueue_add()
2016-08-11 14:10:23 -07:00
Linus Torvalds 3b3ce01a57 A patch for a NULL dereference bug introduced in 4.8-rc1 and a handful
of static checker fixes.
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Merge tag 'ceph-for-4.8-rc2' of https://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "A patch for a NULL dereference bug introduced in 4.8-rc1 and a handful
  of static checker fixes"

* tag 'ceph-for-4.8-rc2' of https://github.com/ceph/ceph-client:
  ceph: initialize pathbase in the !dentry case in encode_caps_cb()
  rbd: nuke the 32-bit pool id check
  rbd: destroy header_oloc in rbd_dev_release()
  ceph: fix null pointer dereference in ceph_flush_snaps()
  libceph: using kfree_rcu() to simplify the code
  libceph: make cancel_generic_request() static
  libceph: fix return value check in alloc_msg_with_page_vector()
2016-08-11 13:53:34 -07:00
Chuck Lever 42691398be nfsd: Fix race between FREE_STATEID and LOCK
When running LTP's nfslock01 test, the Linux client can send a LOCK
and a FREE_STATEID request at the same time. The outcome is:

Frame 324    R OPEN stateid [2,O]

Frame 115004 C LOCK lockowner_is_new stateid [2,O] offset 672000 len 64
Frame 115008 R LOCK stateid [1,L]
Frame 115012 C WRITE stateid [0,L] offset 672000 len 64
Frame 115016 R WRITE NFS4_OK
Frame 115019 C LOCKU stateid [1,L] offset 672000 len 64
Frame 115022 R LOCKU NFS4_OK
Frame 115025 C FREE_STATEID stateid [2,L]
Frame 115026 C LOCK lockowner_is_new stateid [2,O] offset 672128 len 64
Frame 115029 R FREE_STATEID NFS4_OK
Frame 115030 R LOCK stateid [3,L]
Frame 115034 C WRITE stateid [0,L] offset 672128 len 64
Frame 115038 R WRITE NFS4ERR_BAD_STATEID

In other words, the server returns stateid L in a successful LOCK
reply, but it has already released it. Subsequent uses of stateid L
fail.

To address this, protect the generation check in nfsd4_free_stateid
with the st_mutex. This should guarantee that only one of two
outcomes occurs: either LOCK returns a fresh valid stateid, or
FREE_STATEID returns NFS4ERR_LOCKS_HELD.

Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Fix-suggested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-11 15:08:39 -04:00
David A. Long ad05711cec arm64: Remove stack duplicating code from jprobes
Because the arm64 calling standard allows stacked function arguments to be
anywhere in the stack frame, do not attempt to duplicate the stack frame for
jprobes handler functions.

Documentation changes to describe this issue have been broken out into a
separate patch in order to simultaneously address them in other
architecture(s).

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-08-11 17:38:16 +01:00
Josef Bacik 502aa0a5be nfsd: fix dentry refcounting on create
b44061d0b9 introduced a dentry ref counting bug.  Previously we were
grabbing one ref to dchild in nfsd_create(), but with the creation of
nfsd_create_locked() we have a ref for dchild from the lookup in
nfsd_create(), and then another ref in nfsd_create_locked().  The ref
from the lookup in nfsd_create() is never dropped and results in
dentries still in use at unmount.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Fixes: b44061d0b9 "nfsd: reorganize nfsd_create"
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-11 11:42:08 -04:00
Johannes Berg 1ea049b2de bvec: avoid variable shadowing warning
Due to the (indirect) nesting of min(..., min(...)), sparse will
show a variable shadowing warning whenever bvec.h is included.

Avoid that by assigning the inner min() to a temporary variable first.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-11 09:41:35 -06:00
Joe Lawrence 005411ea7e doc: update block/queue-sysfs.txt entries
Add descriptions for dax, io_poll, and write_same_max_bytes files.

Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-11 09:37:23 -06:00
Gabriel Krisman Bertazi c21377f836 nvme: Suspend all queues before deletion
When nvme_delete_queue fails in the first pass of the
nvme_disable_io_queues() loop, we return early, failing to suspend all
of the IO queues.  Later, on the nvme_pci_disable path, this causes us
to disable MSI without actually having freed all the IRQs, which
triggers the BUG_ON in free_msi_irqs(), as show below.

This patch refactors nvme_disable_io_queues to suspend all queues before
start submitting delete queue commands.  This way, we ensure that we
have at least returned every IRQ before continuing with the removal
path.

[  487.529200] kernel BUG at ../drivers/pci/msi.c:368!
cpu 0x46: Vector: 700 (Program Check) at [c0000078c5b83650]
    pc: c000000000627a50: free_msi_irqs+0x90/0x200
    lr: c000000000627a40: free_msi_irqs+0x80/0x200
    sp: c0000078c5b838d0
   msr: 9000000100029033
  current = 0xc0000078c5b40000
  paca    = 0xc000000002bd7600   softe: 0        irq_happened: 0x01
    pid   = 1376, comm = kworker/70:1H
kernel BUG at ../drivers/pci/msi.c:368!
Linux version 4.7.0.mainline+ (root@iod76) (gcc version 5.3.1 20160413
(Ubuntu/IBM 5.3.1-14ubuntu2.1) ) #104 SMP Fri Jul 29 09:20:17 CDT 2016
enter ? for help
[c0000078c5b83920] d0000000363b0cd8 nvme_dev_disable+0x208/0x4f0 [nvme]
[c0000078c5b83a10] d0000000363b12a4 nvme_timeout+0xe4/0x250 [nvme]
[c0000078c5b83ad0] c0000000005690e4 blk_mq_rq_timed_out+0x64/0x110
[c0000078c5b83b40] c00000000056c930 bt_for_each+0x160/0x170
[c0000078c5b83bb0] c00000000056d928 blk_mq_queue_tag_busy_iter+0x78/0x110
[c0000078c5b83c00] c0000000005675d8 blk_mq_timeout_work+0xd8/0x1b0
[c0000078c5b83c50] c0000000000e8cf0 process_one_work+0x1e0/0x590
[c0000078c5b83ce0] c0000000000e9148 worker_thread+0xa8/0x660
[c0000078c5b83d80] c0000000000f2090 kthread+0x110/0x130
[c0000078c5b83e30] c0000000000095f0 ret_from_kernel_thread+0x5c/0x6c

Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: linux-nvme@lists.infradead.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-11 09:35:57 -06:00
Sebastian Andrzej Siewior d52c0569ba x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe()
I made a mistake while converting the driver to the hotplug state
machine and as a result x2apic_cluster_probe() was accessing
cpus_in_cluster before allocating it.

This patch fixes it by setting the cpumask after the allocation the
memory succeeded.

While at it, I marked two functions static which are only used within
this file.

Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 6b2c28471d ("x86/x2apic: Convert to CPU hotplug state machine")
Link: http://lkml.kernel.org/r/1470924515-9444-1-git-send-email-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 16:35:50 +02:00
Frederic Weisbecker 26f2c75cd2 sched/cputime: Fix omitted ticks passed in parameter
Commit:

  f9bcf1e0e0 ("sched/cputime: Fix steal time accounting")

... fixes a leak on steal time accounting but forgets to account
the ticks passed in parameters, assuming there is only one to
take into account.

Let's consider that parameter back.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Wanpeng Li <kernellwp@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: linux-tip-commits@vger.kernel.org
Link: http://lkml.kernel.org/r/20160811125822.GB4214@lerouge
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 16:34:37 +02:00
Austin Christ 6862e6ad95 efi/capsule: Allocate whole capsule into virtual memory
According to UEFI 2.6 section 7.5.3, the capsule should be in contiguous
virtual memory and firmware may consume the capsule immediately. To
correctly implement this functionality, the kernel driver needs to vmap
the entire capsule at the time it is made available to firmware.

The virtual allocation of the capsule update has been changed from kmap,
which was only allocating the first page of the update, to vmap, and
allocates the entire data payload.

Signed-off-by: Austin Christ <austinwc@codeaurora.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Lee, Chun-Yi <jlee@suse.com>
Cc: <stable@vger.kernel.org> # v4.7
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kweh Hock Leong <hock.leong.kweh@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1470912120-22831-3-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 13:55:36 +02:00
Alex Thorlton f72075c9ed x86/platform/uv: Skip UV runtime services mapping in the efi_runtime_disabled case
This problem has actually been in the UV code for a while, but we didn't
catch it until recently, because we had been relying on EFI_OLD_MEMMAP
to allow our systems to boot for a period of time.  We noticed the issue
when trying to kexec a recent community kernel, where we hit this NULL
pointer dereference in efi_sync_low_kernel_mappings():

 [    0.337515] BUG: unable to handle kernel NULL pointer dereference at 0000000000000880
 [    0.346276] IP: [<ffffffff8105df8d>] efi_sync_low_kernel_mappings+0x5d/0x1b0

The problem doesn't show up with EFI_OLD_MEMMAP because we skip the
chunk of setup_efi_state() that sets the efi_loader_signature for the
kexec'd kernel.  When the kexec'd kernel boots, it won't set EFI_BOOT in
setup_arch, so we completely avoid the bug.

We always kexec with noefi on the command line, so this shouldn't be an
issue, but since we're not actually checking for efi_runtime_disabled in
uv_bios_init(), we end up trying to do EFI runtime callbacks when we
shouldn't be. This patch just adds a check for efi_runtime_disabled in
uv_bios_init() so that we don't map in uv_systab when runtime_disabled ==
true.

Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: <stable@vger.kernel.org> # v4.7
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1470912120-22831-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 13:55:36 +02:00
Andy Lutomirski 5bc653b731 x86/efi: Allocate a trampoline if needed in efi_free_boot_services()
On my Dell XPS 13 9350 with firmware 1.4.4 and SGX on, if I boot
Fedora 24's grub2-efi off a hard disk, my first 1MB of RAM looks
like:

 efi: mem00: [Runtime Data       |RUN|  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000000000-0x0000000000000fff] (0MB)
 efi: mem01: [Boot Data          |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000001000-0x0000000000027fff] (0MB)
 efi: mem02: [Loader Data        |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000028000-0x0000000000029fff] (0MB)
 efi: mem03: [Reserved           |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002a000-0x000000000002bfff] (0MB)
 efi: mem04: [Runtime Data       |RUN|  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002c000-0x000000000002cfff] (0MB)
 efi: mem05: [Loader Data        |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002d000-0x000000000002dfff] (0MB)
 efi: mem06: [Conventional Memory|   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002e000-0x0000000000057fff] (0MB)
 efi: mem07: [Reserved           |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000058000-0x0000000000058fff] (0MB)
 efi: mem08: [Conventional Memory|   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000059000-0x000000000009ffff] (0MB)

My EBDA is at 0x2c000, which blocks off everything from 0x2c000 and
up, and my trampoline is 0x6000 bytes (6 pages), so it doesn't fit
in the loader data range at 0x28000.

Without this patch, it panics due to a failure to allocate the
trampoline.  With this patch, it works:

 [  +0.001744] Base memory trampoline at [ffff880000001000] 1000 size 24576

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/998c77b3bf709f3dfed85cb30701ed1a5d8a438b.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 13:53:07 +02:00
Andy Lutomirski 5ff3e2c3c3 x86/boot: Rework reserve_real_mode() to allow multiple tries
If reserve_real_mode() fails, panicing immediately means we're
doomed.  Make it safe to try more than once to allocate the
trampoline:

 - Degrade a failure from panic() to pr_info().  (If we make it to
   setup_real_mode() without reserving the trampoline, we'll panic
   them.)

 - Factor out helpers so that platform code can supply a specific
   address to try.

 - Warn if reserve_real_mode() is called after we're done with the
   memblock allocator.  If that were to happen, we would behave
   unpredictably.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/876e383038f3e9971aa72fd20a4f5da05f9d193d.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:15:01 +02:00
Andy Lutomirski d0de0f685d x86/boot: Defer setup_real_mode() to early_initcall time
There's no need to run setup_real_mode() as early as we run it.
Defer it to the same early_initcall that sets up the page
permissions for the real mode code.

This should be a code size reduction.  More importantly, it give us
a longer window in which we can allocate the real mode trampoline.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fd62f0da4f79357695e9bf3e365623736b05f119.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:15:00 +02:00
Andy Lutomirski 18bc7bd523 x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly
The initialization process for trampoline_cr4_features and
mmu_cr4_features was confusing.  The intent is for mmu_cr4_features
and *trampoline_cr4_features to stay in sync, but
trampoline_cr4_features is NULL until setup_real_mode() runs.  The
old code synchronized *trampoline_cr4_features *twice*, once in
setup_real_mode() and once in setup_arch().  It also initialized
mmu_cr4_features in setup_real_mode(), which causes the actual value
of mmu_cr4_features to potentially depend on when setup_real_mode()
is called.

With this patch, mmu_cr4_features is initialized directly in
setup_arch(), and *trampoline_cr4_features is synchronized to
mmu_cr4_features when the trampoline is set up.

After this patch, it should be safe to defer setup_real_mode().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/d48a263f9912389b957dd495a7127b009259ffe0.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:15:00 +02:00
Andy Lutomirski 007b756053 x86/boot: Run reserve_bios_regions() after we initialize the memory map
reserve_bios_regions() is a quirk that reserves memory that we might
otherwise think is available.  There's no need to run it so early,
and running it before we have the memory map initialized with its
non-quirky inputs makes it hard to make reserve_bios_regions() more
intelligent.

Move it right after we populate the memblock state.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/59f58618911005c799c6c9979ce6ae4881d907c2.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:14:59 +02:00
Aaron Lu 82ba4faca1 x86/irq: Do not substract irq_tlb_count from irq_call_count
Since commit:

  52aec3308d ("x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR")

the TLB remote shootdown is done through call function vector. That
commit didn't take care of irq_tlb_count, which a later commit:

  fd0f586972 ("x86: Distinguish TLB shootdown interrupts from other functions call interrupts")

... tried to fix.

The fix assumes every increase of irq_tlb_count has a corresponding
increase of irq_call_count. So the irq_call_count is always bigger than
irq_tlb_count and we could substract irq_tlb_count from irq_call_count.

Unfortunately this is not true for the smp_call_function_single() case.
The IPI is only sent if the target CPU's call_single_queue is empty when
adding a csd into it in generic_exec_single. That means if two threads
are both adding flush tlb csds to the same CPU's call_single_queue, only
one IPI is sent. In other words, the irq_call_count is incremented by 1
but irq_tlb_count is incremented by 2. Over time, irq_tlb_count will be
bigger than irq_call_count and the substract will produce a very large
irq_call_count value due to overflow.

Considering that:

  1) it's not worth to send more IPIs for the sake of accurate counting of
     irq_call_count in generic_exec_single();

  2) it's not easy to tell if the call function interrupt is for TLB
     shootdown in __smp_call_function_single_interrupt().

Not to exclude TLB shootdown from call function count seems to be the
simplest fix and this patch just does that.

This bug was found by LKP's cyclic performance regression tracking recently
with the vm-scalability test suite. I have bisected to commit:

  3dec0ba0be ("mm/rmap: share the i_mmap_rwsem")

This commit didn't do anything wrong but revealed the irq_call_count
problem. IIUC, the commit makes rwc->remap_one in rmap_walk_file
concurrent with multiple threads.  When remap_one is try_to_unmap_one(),
then multiple threads could queue flush TLB to the same CPU but only
one IPI will be sent.

Since the commit was added in Linux v3.19, the counting problem only
shows up from v3.19 onwards.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Cc: Alex Shi <alex.shi@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Link: http://lkml.kernel.org/r/20160811074430.GA18163@aaronlu.sh.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:14:59 +02:00
Dave Hansen ace7fab7a6 x86/mm: Fix swap entry comment and macro
A recent patch changed the format of a swap PTE.

The comment explaining the format of the swap PTE is wrong about
the bits used for the swap type field.  Amusingly, the ASCII art
and the patch description are correct, but the comment itself
is wrong.

As I was looking at this, I also noticed that the
SWP_OFFSET_FIRST_BIT has an off-by-one error.  This does not
really hurt anything.  It just wasted a bit of space in the PTE,
giving us 2^59 bytes of addressable space in our swapfiles
instead of 2^60.  But, it doesn't match with the comments, and it
wastes a bit of space, so fix it.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Fixes: 00839ee3b2 ("x86/mm: Move swap offset/type up in PTE to work around erratum")
Link: http://lkml.kernel.org/r/20160810172325.E56AD7DA@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:04:10 +02:00
Wanpeng Li f9bcf1e0e0 sched/cputime: Fix steal time accounting
Commit:

  5743021831 ("sched/cputime: Count actually elapsed irq & softirq time")

... didn't take steal time into consideration with passing the noirqtime
kernel parameter.

As Paolo pointed out before:

| Why not? If idle=poll, for example, any time the guest is suspended (and
| thus cannot poll) does count as stolen time.

This patch fixes it by reducing steal time from idle time accounting when
the noirqtime parameter is true. The average idle time drops from 56.8%
to 54.75% for nohz idle kvm guest(noirqtime, idle=poll, four vCPUs running
on one pCPU).

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1470893795-3527-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:02:14 +02:00
Nicolas Iooss 62d16b5a3f x86/mm/kaslr: Fix -Wformat-security warning
debug_putstr() is used to output strings without using printf-like
formatting but debug_putstr(v) is defined as early_printk(v) in
arch/x86/lib/kaslr.c.

This makes clang reports the following warning when building
with -Wformat-security:

    arch/x86/lib/kaslr.c:57:15: warning: format string is not a string
    literal (potentially insecure) [-Wformat-security]
            debug_putstr(purpose);
                         ^~~~~~~

Fix this by using "%s" in early_printk().

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160806102039.27221-1-nicolas.iooss_linux@m4x.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 10:58:12 +02:00
Arnd Bergmann 12beb34671 Merge tag 'pxa-fixes-v4.8' of https://github.com/rjarzmik/linux into randconfig-4.8
This is the pxa changes for v4.8 cycle.

This is a tiny fix couple to enable changes in includes in
gpio API without breaking pxa boards.

* tag 'pxa-fixes-v4.8' of https://github.com/rjarzmik/linux:
  ARM: pxa: add module.h for corgi symbol_get/symbol_put usage
  ARM: pxa: add module.h for spitz symbol_get/symbol_put usage
2016-08-11 08:43:03 +02:00
Linus Torvalds 85e97be32c Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "8 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/slub.c: run free_partial() outside of the kmem_cache_node->list_lock
  rmap: fix compound check logic in page_remove_file_rmap
  mm, rmap: fix false positive VM_BUG() in page_add_file_rmap()
  mm/page_alloc.c: recalculate some of node threshold when on/offline memory
  mm/page_alloc.c: fix wrong initialization when sysctl_min_unmapped_ratio changes
  thp: move shmem_huge_enabled() outside of SYSFS ifdef
  revert "ARM: keystone: dts: add psci command definition"
  rapidio: dereferencing an error pointer
2016-08-10 16:41:09 -07:00
Chris Wilson 6039892396 mm/slub.c: run free_partial() outside of the kmem_cache_node->list_lock
With debugobjects enabled and using SLAB_DESTROY_BY_RCU, when a
kmem_cache_node is destroyed the call_rcu() may trigger a slab
allocation to fill the debug object pool (__debug_object_init:fill_pool).

Everywhere but during kmem_cache_destroy(), discard_slab() is performed
outside of the kmem_cache_node->list_lock and avoids a lockdep warning
about potential recursion:

  =============================================
  [ INFO: possible recursive locking detected ]
  4.8.0-rc1-gfxbench+ #1 Tainted: G     U
  ---------------------------------------------
  rmmod/8895 is trying to acquire lock:
   (&(&n->list_lock)->rlock){-.-...}, at: [<ffffffff811c80d7>] get_partial_node.isra.63+0x47/0x430

  but task is already holding lock:
   (&(&n->list_lock)->rlock){-.-...}, at: [<ffffffff811cbda4>] __kmem_cache_shutdown+0x54/0x320

  other info that might help us debug this:
  Possible unsafe locking scenario:
        CPU0
        ----
   lock(&(&n->list_lock)->rlock);
   lock(&(&n->list_lock)->rlock);

   *** DEADLOCK ***
   May be due to missing lock nesting notation
   5 locks held by rmmod/8895:
   #0:  (&dev->mutex){......}, at: driver_detach+0x42/0xc0
   #1:  (&dev->mutex){......}, at: driver_detach+0x50/0xc0
   #2:  (cpu_hotplug.dep_map){++++++}, at: get_online_cpus+0x2d/0x80
   #3:  (slab_mutex){+.+.+.}, at: kmem_cache_destroy+0x3c/0x220
   #4:  (&(&n->list_lock)->rlock){-.-...}, at: __kmem_cache_shutdown+0x54/0x320

  stack backtrace:
  CPU: 6 PID: 8895 Comm: rmmod Tainted: G     U          4.8.0-rc1-gfxbench+ #1
  Hardware name: Gigabyte Technology Co., Ltd. H87M-D3H/H87M-D3H, BIOS F11 08/18/2015
  Call Trace:
    __lock_acquire+0x1646/0x1ad0
    lock_acquire+0xb2/0x200
    _raw_spin_lock+0x36/0x50
    get_partial_node.isra.63+0x47/0x430
    ___slab_alloc.constprop.67+0x1a7/0x3b0
    __slab_alloc.isra.64.constprop.66+0x43/0x80
    kmem_cache_alloc+0x236/0x2d0
    __debug_object_init+0x2de/0x400
    debug_object_activate+0x109/0x1e0
    __call_rcu.constprop.63+0x32/0x2f0
    call_rcu+0x12/0x20
    discard_slab+0x3d/0x40
    __kmem_cache_shutdown+0xdb/0x320
    shutdown_cache+0x19/0x60
    kmem_cache_destroy+0x1ae/0x220
    i915_gem_load_cleanup+0x14/0x40 [i915]
    i915_driver_unload+0x151/0x180 [i915]
    i915_pci_remove+0x14/0x20 [i915]
    pci_device_remove+0x34/0xb0
    __device_release_driver+0x95/0x140
    driver_detach+0xb6/0xc0
    bus_remove_driver+0x53/0xd0
    driver_unregister+0x27/0x50
    pci_unregister_driver+0x25/0x70
    i915_exit+0x1a/0x1e2 [i915]
    SyS_delete_module+0x193/0x1f0
    entry_SYSCALL_64_fastpath+0x1c/0xac

Fixes: 52b4b950b5 ("mm: slab: free kmem_cache_node after destroy sysfs file")
Link: http://lkml.kernel.org/r/1470759070-18743-1-git-send-email-chris@chris-wilson.co.uk
Reported-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Gordon <david.s.gordon@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Steve Capper 57dea93ac4 rmap: fix compound check logic in page_remove_file_rmap
In page_remove_file_rmap(.) we have the following check:

  VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page);

This is meant to check for either HugeTLB pages or THP when a compound
page is passed in.

Unfortunately, if one disables CONFIG_TRANSPARENT_HUGEPAGE, then
PageTransHuge(.) will always return false, provoking BUGs when one runs
the libhugetlbfs test suite.

This patch replaces PageTransHuge(), with PageHead() which will work for
both HugeTLB and THP.

Fixes: dd78fedde4 ("rmap: support file thp")
Link: http://lkml.kernel.org/r/1470838217-5889-1-git-send-email-steve.capper@arm.com
Signed-off-by: Steve Capper <steve.capper@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Huang Shijie <shijie.huang@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Kirill A. Shutemov c8efc390c1 mm, rmap: fix false positive VM_BUG() in page_add_file_rmap()
PageTransCompound() doesn't distinguish THP from from any other type of
compound pages.  This can lead to false-positive VM_BUG_ON() in
page_add_file_rmap() if called on compound page from a driver[1].

I think we can exclude such cases by checking if the page belong to a
mapping.

The VM_BUG_ON_PAGE() is downgraded to VM_WARN_ON_ONCE().  This path
should not cause any harm to non-THP page, but good to know if we step
on anything else.

[1] http://lkml.kernel.org/r/c711e067-0bff-a6cb-3c37-04dfe77d2db1@redhat.com

Link: http://lkml.kernel.org/r/20160810161345.GA67522@black.fi.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Laura Abbott <labbott@redhat.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Joonsoo Kim 6423aa8192 mm/page_alloc.c: recalculate some of node threshold when on/offline memory
Some of node threshold depends on number of managed pages in the node.
When memory is going on/offline, it can be changed and we need to adjust
them.

Add recalculation to appropriate places and clean-up related functions
for better maintenance.

Link: http://lkml.kernel.org/r/1470724248-26780-2-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Joonsoo Kim 81cbcbc2d8 mm/page_alloc.c: fix wrong initialization when sysctl_min_unmapped_ratio changes
Before resetting min_unmapped_pages, we need to initialize
min_unmapped_pages rather than min_slab_pages.

Fixes: a5f5f91da6 (mm: convert zone_reclaim to node_reclaim)
Link: http://lkml.kernel.org/r/1470724248-26780-1-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Arnd Bergmann 3b33719c9b thp: move shmem_huge_enabled() outside of SYSFS ifdef
The newly introduced shmem_huge_enabled() function has two definitions,
but neither of them is visible if CONFIG_SYSFS is disabled, leading to a
build error:

  mm/khugepaged.o: In function `khugepaged':
  khugepaged.c:(.text.khugepaged+0x3ca): undefined reference to `shmem_huge_enabled'

This changes the #ifdef guards around the definition to match those that
are used in the header file.

Fixes: e496cf3d78 ("thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE")
Link: http://lkml.kernel.org/r/20160809123638.1357593-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Andrew Morton a545de5ce2 revert "ARM: keystone: dts: add psci command definition"
Revert commit 51d5d12b8f ("ARM: keystone: dts: add psci command
definition"), which was inadvertently added twice.

Cc: Russell King - ARM Linux <linux@armlinux.org.uk>
Cc: Vitaly Andrianov <vitalya@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Dan Carpenter 73984137d3 rapidio: dereferencing an error pointer
Original patch: https://lkml.org/lkml/2016/8/4/32

If riocm_ch_alloc() fails then we end up dereferencing the error
pointer.

The problem is that we're not unwinding in the reverse order from how we
allocate things so it gets confusing.  I've changed this around so now
"ch" is NULL when we are done with it after we call riocm_put_channel().
That way we can check if it's NULL and avoid calling riocm_put_channel()
on it twice.

I renamed err_nodev to err_put_new_ch so that it better reflects what
the goto does.

Then because we had flipping things around, it means we don't neeed to
initialize the pointers to NULL and we can remove an if statement and
pull things in an indent level.

Link: http://lkml.kernel.org/r/20160805152406.20713-1-alexandre.bounine@idt.com
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Barry Wood <barry.wood@idt.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-10 16:40:56 -07:00
Dan Williams d8d378fa1a tools/testing/nvdimm: fix SIGTERM vs hotplug crash
The unit tests crash when hotplug races the previous probe. This race
requires that the loading of the nfit_test module be terminated with
SIGTERM, and the module to be unloaded while the ars scan is still
running.

In contrast to the normal nfit driver, the unit test calls
acpi_nfit_init() twice to simulate hotplug, whereas the nominal case
goes through the acpi_nfit_notify() event handler.  The
acpi_nfit_notify() path is careful to flush the previous region
registration before servicing the hotplug event. The unit test was
missing this guarantee.

 BUG: unable to handle kernel NULL pointer dereference at           (null)
 IP: [<ffffffff810cdce7>] pwq_activate_delayed_work+0x47/0x170
 [..]
 Call Trace:
  [<ffffffff810ce186>] pwq_dec_nr_in_flight+0x66/0xa0
  [<ffffffff810ce490>] process_one_work+0x2d0/0x680
  [<ffffffff810ce331>] ? process_one_work+0x171/0x680
  [<ffffffff810ce88e>] worker_thread+0x4e/0x480
  [<ffffffff810ce840>] ? process_one_work+0x680/0x680
  [<ffffffff810ce840>] ? process_one_work+0x680/0x680
  [<ffffffff810d5343>] kthread+0xf3/0x110
  [<ffffffff8199846f>] ret_from_fork+0x1f/0x40
  [<ffffffff810d5250>] ? kthread_create_on_node+0x230/0x230

Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-08-10 15:59:09 -07:00