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  1. 06 May, 2019 8 commits
  3. 05 May, 2019 5 commits
    • Linus Torvalds's avatar
      Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 7178fb0b
      Linus Torvalds authored 
      Pull perf fixes from Ingo Molnar:
 "I'd like to apologize for this very late pull request: I was dithering
  through the week whether to send the fixes, and then yesterday Jiri's
  crash fix for a regression introduced in this cycle clearly marked
  perf/urgent as 'must merge now'.

  Most of the commits are tooling fixes, plus there's three kernel fixes
  via four commits:

    - race fix in the Intel PEBS code

    - fix an AUX bug and roll back a previous attempt

    - fix AMD family 17h generic HW cache-event perf counters

  The largest diffstat contribution comes from the AMD fix - a new event
  table is introduced, which is a fairly low risk change but has a large
  linecount"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Fix race in intel_pmu_disable_event()
  perf/x86/intel/pt: Remove software double buffering PMU capability
  perf/ring_buffer: Fix AUX software double buffering
  perf tools: Remove needless asm/unistd.h include fixing build in some places
  tools arch uapi: Copy missing unistd.h headers for arc, hexagon and riscv
  tools build: Add -ldl to the disassembler-four-args feature test
  perf cs-etm: Always allocate memory for cs_etm_queue::prev_packet
  perf cs-etm: Don't check cs_etm_queue::prev_packet validity
  perf report: Report OOM in status line in the GTK UI
  perf bench numa: Add define for RUSAGE_THREAD if not present
  tools lib traceevent: Change tag string for error
  perf annotate: Fix build on 32 bit for BPF annotation
  tools uapi x86: Sync vmx.h with the kernel
  perf bpf: Return value with unlocking in perf_env__find_btf()
  MAINTAINERS: Include vendor specific files under arch/*/events/*
  perf/x86/amd: Update generic hardware cache events for Family 17h
      7178fb0b
    • Linus Torvalds's avatar
      Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 70c9fb57
      Linus Torvalds authored 
      Pull scheduler fix from Ingo Molnar:
 "Fix a kobject memory leak in the cpufreq code"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/cpufreq: Fix kobject memleak
      70c9fb57
    • Linus Torvalds's avatar
      Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 13369e83
      Linus Torvalds authored 
      Pull x86 fix from Ingo Molnar:
 "Disable function tracing during early SME setup to fix a boot crash on
  SME-enabled kernels running distro kernels (some of which have
  function tracing enabled)"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/mem_encrypt: Disable all instrumentation for early SME setup
      13369e83
    • Linus Torvalds's avatar
      Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · 51987aff
      Linus Torvalds authored 
      Pull vfs fixes from Al Viro:

 - a couple of ->i_link use-after-free fixes

 - regression fix for wrong errno on absent device name in mount(2)
   (this cycle stuff)

 - ancient UFS braino in large GID handling on Solaris UFS images (bogus
   cut'n'paste from large UID handling; wrong field checked to decide
   whether we should look at old (16bit) or new (32bit) field)

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour
  Abort file_remove_privs() for non-reg. files
  [fix] get rid of checking for absent device name in vfs_get_tree()
  apparmorfs: fix use-after-free on symlink traversal
  securityfs: fix use-after-free on symlink traversal
      51987aff
    • Jiri Olsa's avatar
      perf/x86/intel: Fix race in intel_pmu_disable_event() · 6f55967a
      Jiri Olsa authored 
      New race in x86_pmu_stop() was introduced by replacing the
atomic __test_and_clear_bit() of cpuc->active_mask by separate
test_bit() and __clear_bit() calls in the following commit:

  3966c3fe ("x86/perf/amd: Remove need to check "running" bit in NMI handler")

The race causes panic for PEBS events with enabled callchains:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  ...
  RIP: 0010:perf_prepare_sample+0x8c/0x530
  Call Trace:
   <NMI>
   perf_event_output_forward+0x2a/0x80
   __perf_event_overflow+0x51/0xe0
   handle_pmi_common+0x19e/0x240
   intel_pmu_handle_irq+0xad/0x170
   perf_event_nmi_handler+0x2e/0x50
   nmi_handle+0x69/0x110
   default_do_nmi+0x3e/0x100
   do_nmi+0x11a/0x180
   end_repeat_nmi+0x16/0x1a
  RIP: 0010:native_write_msr+0x6/0x20
  ...
   </NMI>
   intel_pmu_disable_event+0x98/0xf0
   x86_pmu_stop+0x6e/0xb0
   x86_pmu_del+0x46/0x140
   event_sched_out.isra.97+0x7e/0x160
  ...

The event is configured to make samples from PEBS drain code,
but when it's disabled, we'll go through NMI path instead,
where data->callchain will not get allocated and we'll crash:

          x86_pmu_stop
            test_bit(hwc->idx, cpuc->active_mask)
            intel_pmu_disable_event(event)
            {
              ...
              intel_pmu_pebs_disable(event);
              ...

EVENT OVERFLOW ->  <NMI>
                     intel_pmu_handle_irq
                       handle_pmi_common
   TEST PASSES ->        test_bit(bit, cpuc->active_mask))
                           perf_event_overflow
                             perf_prepare_sample
                             {
                               ...
                               if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY))
                                     data->callchain = perf_callchain(event, regs);

         CRASH ->              size += data->callchain->nr;
                             }
                   </NMI>
              ...
              x86_pmu_disable_event(event)
            }

            __clear_bit(hwc->idx, cpuc->active_mask);

Fixing this by disabling the event itself before setting
off the PEBS bit.
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Arcari <darcari@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Lendacky Thomas <Thomas.Lendacky@amd.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>
Fixes: 3966c3fe ("x86/perf/amd: Remove need to check "running" bit in NMI handler")
Link: http://lkml.kernel.org/r/20190504151556.31031-1-jolsa@kernel.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6f55967a
  5. 04 May, 2019 1 commit
  7. 03 May, 2019 26 commits
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