================================================================== BUG: KCSAN: data-race in __change_pid / perf_event_switch_output write to 0xffff8881296de8e8 of 8 bytes by task 6369 on cpu 1: __change_pid+0xe9/0x1c0 kernel/pid.c:356 detach_pid+0x1c/0x30 kernel/pid.c:372 __unhash_process kernel/exit.c:129 [inline] __exit_signal kernel/exit.c:201 [inline] release_task+0x6c3/0xc30 kernel/exit.c:258 wait_task_zombie kernel/exit.c:1188 [inline] wait_consider_task+0x116b/0x1670 kernel/exit.c:1415 do_wait_thread kernel/exit.c:1478 [inline] __do_wait+0x100/0x500 kernel/exit.c:1596 do_wait+0xaf/0x270 kernel/exit.c:1630 kernel_wait4+0x164/0x1d0 kernel/exit.c:1789 __do_sys_wait4 kernel/exit.c:1817 [inline] __se_sys_wait4 kernel/exit.c:1813 [inline] __x64_sys_wait4+0x94/0x120 kernel/exit.c:1813 x64_sys_call+0x61d/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:62 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff8881296de8e8 of 8 bytes by task 12742 on cpu 0: pid_alive include/linux/pid.h:263 [inline] perf_event_pid_type kernel/events/core.c:1334 [inline] perf_event_pid kernel/events/core.c:1341 [inline] perf_event_switch_output+0x19e/0x390 kernel/events/core.c:9061 perf_iterate_sb_cpu kernel/events/core.c:8003 [inline] perf_iterate_sb+0x34b/0x640 kernel/events/core.c:8032 perf_event_switch kernel/events/core.c:9108 [inline] __perf_event_task_sched_in+0x789/0x7f0 kernel/events/core.c:4018 perf_event_task_sched_in include/linux/perf_event.h:1473 [inline] finish_task_switch+0x218/0x2b0 kernel/sched/core.c:5277 context_switch kernel/sched/core.c:5411 [inline] __schedule+0x5e8/0x940 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x55/0xc0 kernel/sched/core.c:6837 exit_to_user_mode_loop kernel/entry/common.c:102 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9f/0x130 kernel/entry/common.c:218 do_syscall_64+0xda/0x1d0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0xffff8881040459c0 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 12742 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-10713-g2a8120d7b482 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 ==================================================================