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KCSAN: data-race in perf_event_exit_event / perf_event_exit_event (4)

Status: auto-obsoleted due to no activity on 2023/08/01 07:53
Subsystems: perf
[Documentation on labels]
First crash: 313d, last: 311d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in perf_event_exit_event / perf_event_exit_event (2) perf 1 828d 828d 0/26 auto-closed as invalid on 2022/03/02 02:45
upstream KCSAN: data-race in perf_event_exit_event / perf_event_exit_event perf 1 941d 941d 0/26 auto-closed as invalid on 2021/11/09 11:06
upstream KCSAN: data-race in perf_event_exit_event / perf_event_exit_event (3) perf 1 643d 643d 0/26 auto-closed as invalid on 2022/09/03 15:29

Sample crash report:
==================================================================
BUG: KCSAN: data-race in perf_event_exit_event / perf_event_exit_event

write to 0xffff88812216be8c of 4 bytes by task 8539 on cpu 1:
 perf_event_wakeup kernel/events/core.c:6628 [inline]
 perf_event_exit_event+0x2ab/0x400 kernel/events/core.c:12984
 perf_event_exit_task_context kernel/events/core.c:13050 [inline]
 perf_event_exit_task+0x3d1/0x520 kernel/events/core.c:13081
 do_exit+0x60f/0x1670 kernel/exit.c:883
 do_group_exit+0x101/0x150 kernel/exit.c:1024
 get_signal+0xeb7/0xff0 kernel/signal.c:2876
 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:308
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812216be8c of 4 bytes by task 8541 on cpu 0:
 perf_event_wakeup kernel/events/core.c:6626 [inline]
 perf_event_exit_event+0x362/0x400 kernel/events/core.c:12993
 perf_event_exit_task_context kernel/events/core.c:13050 [inline]
 perf_event_exit_task+0x3d1/0x520 kernel/events/core.c:13081
 do_exit+0x60f/0x1670 kernel/exit.c:883
 do_group_exit+0x101/0x150 kernel/exit.c:1024
 get_signal+0xeb7/0xff0 kernel/signal.c:2876
 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:308
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8541 Comm: syz-executor.1 Not tainted 6.4.0-syzkaller-01224-g1ef6663a587b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/27 07:48 upstream 1ef6663a587b 4cd5bb25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in perf_event_exit_event / perf_event_exit_event
2023/06/25 16:29 upstream a92b7d26c743 79782afc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in perf_event_exit_event / perf_event_exit_event
* Struck through repros no longer work on HEAD.