Gh0st
/
linux
mirror of https://github.com/torvalds/linux.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
linux/arch/x86/events
History
Kan Liang b0823d5fba perf/x86/intel: Fix crash in icl_update_topdown_event() 
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
 		2025-06-13 09:38:06 +02:00
..
amd Core x86 updates for v6.16: 2025-05-26 16:04:17 -07:00
intel perf/x86/intel: Fix crash in icl_update_topdown_event() 2025-06-13 09:38:06 +02:00
zhaoxin Core x86 updates for v6.16: 2025-05-26 16:04:17 -07:00
Kconfig perf/x86/Kconfig: Fix indentation in the Kconfig file 2022-05-25 15:54:26 +02:00
Makefile perf/x86: Move branch classifier 2022-08-27 00:05:44 +02:00
core.c Core x86 updates for v6.16: 2025-05-26 16:04:17 -07:00
msr.c x86/msr: Add explicit includes of <asm/msr.h> 2025-05-02 10:23:47 +02:00
perf_event.h Core x86 updates for v6.16: 2025-05-26 16:04:17 -07:00
perf_event_flags.h perf: Extend the bit width of the arch-specific flag 2025-04-08 20:55:49 +02:00
probe.c x86/msr: Add explicit includes of <asm/msr.h> 2025-05-02 10:23:47 +02:00
probe.h perf/x86/rapl: Add msr mask support 2021-02-10 14:44:54 +01:00
rapl.c x86/msr: Add explicit includes of <asm/msr.h> 2025-05-02 10:23:47 +02:00
utils.c x86/msr: Add explicit includes of <asm/msr.h> 2025-05-02 10:23:47 +02:00