syzbot

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BUG: KCSAN: data-race in fasync_remove_entry / perf_swevent_hrtimer

write to 0xffff88811e704f00 of 8 bytes by task 28070 on cpu 1:
 fasync_remove_entry+0xd5/0x140 fs/fcntl.c:884
 fasync_helper+0x92/0xc0 fs/fcntl.c:983
 perf_fasync+0x5a/0x80 kernel/events/core.c:6190
 __fput+0x420/0x460 fs/file_table.c:278
 ____fput+0x11/0x20 fs/file_table.c:314
 task_work_run+0x8e/0x110 kernel/task_work.c:135
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:239 [inline]
 __prepare_exit_to_usermode+0x1c6/0x230 arch/x86/entry/common.c:269
 __syscall_return_slowpath+0x47/0x60 arch/x86/entry/common.c:352
 do_syscall_64+0x5d/0xb0 arch/x86/entry/common.c:393
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88811e704f00 of 8 bytes by interrupt on cpu 0:
 __perf_event_overflow kernel/events/core.c:8748 [inline]
 perf_swevent_hrtimer+0x378/0x4a0 kernel/events/core.c:10130
 __run_hrtimer+0x154/0x4b0 kernel/time/hrtimer.c:1520
 __hrtimer_run_queues kernel/time/hrtimer.c:1584 [inline]
 hrtimer_interrupt+0x37c/0xa40 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x280 arch/x86/kernel/apic/apic.c:1097
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 sysvec_apic_timer_interrupt+0xb5/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:585

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28071 Comm: syz-executor.4 Not tainted 5.8.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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