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BUG: KCSAN: data-race in fasync_remove_entry / kill_fasync

write to 0xffff8880a1396f00 of 8 bytes by task 14390 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:6002
 __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:164
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a1396f00 of 8 bytes by interrupt on cpu 0:
 kill_fasync+0x3f/0x180 fs/fcntl.c:1019
 perf_event_wakeup+0x11f/0x160 kernel/events/core.c:6042
 perf_pending_event+0x12d/0x170 kernel/events/core.c:6098
 irq_work_run_list+0x136/0x190 kernel/irq_work.c:156
 irq_work_run+0x48/0xa0 kernel/irq_work.c:172
 smp_irq_work_interrupt+0x3f/0x100 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:860
 snd_timer_find+0x1/0x1a0 sound/core/timer.c:129
 snd_seq_timer_open+0x152/0x2f0 sound/core/seq/seq_timer.c:281
 queue_use+0x10d/0x1a0 sound/core/seq/seq_queue.c:489
 snd_seq_queue_alloc+0x1e0/0x330 sound/core/seq/seq_queue.c:176
 snd_seq_ioctl_create_queue+0x5e/0x170 sound/core/seq/seq_clientmgr.c:1548
 snd_seq_kernel_client_ctl+0xbd/0xf0 sound/core/seq/seq_clientmgr.c:2353
 alloc_seq_queue.isra.0+0xc6/0x130 sound/core/seq/oss/seq_oss_init.c:357
 snd_seq_oss_open+0x1fc/0x550 sound/core/seq/oss/seq_oss_init.c:215
 odev_open+0x56/0x80 sound/core/seq/oss/seq_oss.c:125
 soundcore_open+0x30b/0x410 sound/sound_core.c:593
 chrdev_open+0x150/0x380 fs/char_dev.c:414
 do_dentry_open+0x301/0x970 fs/open.c:797
 vfs_open+0x62/0x80 fs/open.c:914
 do_last fs/namei.c:3420 [inline]
 path_openat+0xf9f/0x3580 fs/namei.c:3537
 do_filp_open+0x11e/0x1b0 fs/namei.c:3567
 do_sys_open+0x3b3/0x4f0 fs/open.c:1097
 __do_sys_openat fs/open.c:1124 [inline]
 __se_sys_openat fs/open.c:1118 [inline]
 __x64_sys_openat+0x62/0x80 fs/open.c:1118
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14393 Comm: syz-executor.2 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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