MIRRORS/linux-yocto
1
0
Fork 0
mirror of git://git.yoctoproject.org/linux-yocto.git synced 2025-10-23 07:23:12 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

perf/x86/intel: Fix crash in icl_update_topdown_event()

Browse Source 
commit b0823d5fba upstream.

The perf_fuzzer found a hard-lockup crash on a RaptorLake machine:

  Oops: general protection fault, maybe for address 0xffff89aeceab400: 0000
  CPU: 23 UID: 0 PID: 0 Comm: swapper/23
  Tainted: [W]=WARN
  Hardware name: Dell Inc. Precision 9660/0VJ762
  RIP: 0010:native_read_pmc+0x7/0x40
  Code: cc e8 8d a9 01 00 48 89 03 5b cd cc cc cc cc 0f 1f ...
  RSP: 000:fffb03100273de8 EFLAGS: 00010046
  ....
  Call Trace:
    <TASK>
    icl_update_topdown_event+0x165/0x190
    ? ktime_get+0x38/0xd0
    intel_pmu_read_event+0xf9/0x210
    __perf_event_read+0xf9/0x210

CPUs 16-23 are E-core CPUs that don't support the perf metrics feature.
The icl_update_topdown_event() should not be invoked on these CPUs.

It's a regression of commit:

  f9bdf1f953 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")

The bug introduced by that commit is that the is_topdown_event() function
is mistakenly used to replace the is_topdown_count() call to check if the
topdown functions for the perf metrics feature should be invoked.

Fix it.

Fixes: f9bdf1f953 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
Closes: https://lore.kernel.org/lkml/352f0709-f026-cd45-e60c-60dfd97f73f3@maine.edu/
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org # v6.15+
Link: https://lore.kernel.org/r/20250612143818.2889040-1-kan.liang@linux.intel.com
[ omitted PEBS check ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Angel Adetula <angeladetula@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kan Liang 2025-06-12 07:38:18 -07:00 committed by Greg Kroah-Hartman
parent ff27e23b31
commit e97c45c770
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/events/intel/core.c
View File

@ -2793,7 +2793,7 @@ static void intel_pmu_read_event(struct perf_event *event)
if (pmu_enabled)
intel_pmu_disable_all();
if (is_topdown_event(event))
if (is_topdown_count(event))
static_call(intel_pmu_update_topdown_event)(event);
else
intel_pmu_drain_pebs_buffer();