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BUG: KCSAN: data-race in fasync_remove_entry / kill_fasync

write to 0xffff8880a9910f00 of 8 bytes by task 13783 on cpu 1:
 fasync_remove_entry+0xb7/0x120 fs/fcntl.c:884
 fasync_helper+0xc9/0xd6 fs/fcntl.c:983
 perf_fasync+0x64/0x90 kernel/events/core.c:6187
 __fput+0x455/0x500 fs/file_table.c:277
 ____fput+0x1b/0x30 fs/file_table.c:313
 task_work_run+0xba/0x120 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2ae/0x2c0 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x38b/0x3b0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a9910f00 of 8 bytes by interrupt on cpu 0:
 kill_fasync+0x3c/0x170 fs/fcntl.c:1021
 perf_event_wakeup+0x115/0x160 kernel/events/core.c:6227
 perf_pending_event+0x129/0x170 kernel/events/core.c:6283
 irq_work_run_list+0x13e/0x190 kernel/irq_work.c:157
 irq_work_run+0x43/0x90 kernel/irq_work.c:174
 smp_irq_work_interrupt+0x3b/0xf0 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:860

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13784 Comm: syz-executor.0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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