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BUG: KCSAN: data-race in __perf_event_overflow / fasync_remove_entry

write to 0xffff8880a4e8a6f8 of 8 bytes by task 8322 on cpu 1:
 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:5915
 __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 0xffff8880a4e8a6f8 of 8 bytes by interrupt on cpu 0:
 __perf_event_overflow+0x11d/0x200 kernel/events/core.c:8190
 perf_swevent_hrtimer+0x261/0x280 kernel/events/core.c:9574
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x288/0x600 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
 arch_local_irq_enable arch/x86/include/asm/paravirt.h:766 [inline]
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
 _raw_spin_unlock_irq+0x4e/0x80 kernel/locking/spinlock.c:199
 finish_lock_switch kernel/sched/core.c:3123 [inline]
 finish_task_switch+0x7b/0x260 kernel/sched/core.c:3223
 context_switch kernel/sched/core.c:3387 [inline]
 __schedule+0x319/0x640 kernel/sched/core.c:4069
 schedule+0x47/0xd0 kernel/sched/core.c:4136
 freezable_schedule include/linux/freezer.h:172 [inline]
 futex_wait_queue_me+0x18d/0x290 kernel/futex.c:2627
 futex_wait+0x19b/0x3f0 kernel/futex.c:2733
 do_futex+0xe9/0x18d0 kernel/futex.c:3644

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8324 Comm: syz-executor.5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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