================================================================== BUG: KCSAN: data-race in __perf_event_overflow / fasync_remove_entry write to 0xffff8880b4d116f8 of 8 bytes by task 22907 on cpu 0: fasync_remove_entry+0xba/0x120 fs/fcntl.c:882 fasync_helper+0xcf/0xdc fs/fcntl.c:981 perf_fasync+0x6c/0xa0 kernel/events/core.c:5917 __fput+0x46a/0x520 fs/file_table.c:277 ____fput+0x1f/0x30 fs/file_table.c:313 task_work_run+0xf6/0x130 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880b4d116f8 of 8 bytes by interrupt on cpu 1: __perf_event_overflow+0x11d/0x200 kernel/events/core.c:8192 perf_swevent_hrtimer+0x261/0x280 kernel/events/core.c:9576 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 should_watch kernel/kcsan/core.c:214 [inline] should_watch kernel/kcsan/core.c:202 [inline] check_access kernel/kcsan/core.c:465 [inline] __tsan_read8+0xb4/0x100 kernel/kcsan/core.c:596 should_fail+0x63/0x45d lib/fault-inject.c:117 should_fail_futex kernel/futex.c:297 [inline] get_futex_key+0x7c4/0xa10 kernel/futex.c:540 futex_wait_setup+0x71/0x210 kernel/futex.c:2674 futex_wait+0x163/0x3f0 kernel/futex.c:2728 do_futex+0xe9/0x18d0 kernel/futex.c:3644 __do_sys_futex kernel/futex.c:3705 [inline] __se_sys_futex kernel/futex.c:3673 [inline] __x64_sys_futex+0x2cd/0x3f0 kernel/futex.c:3673 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 22929 Comm: syz-executor.4 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================