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BUG: KCSAN: data-race in poll_schedule_timeout.constprop.0 / pollwake

read to 0xffffc900018a7a20 of 4 bytes by task 13720 on cpu 0:
 poll_schedule_timeout.constprop.0+0x50/0xc0 fs/select.c:242
 do_select+0xd7f/0x1020 fs/select.c:603
 core_sys_select+0x381/0x550 fs/select.c:677
 do_pselect.constprop.0+0x11d/0x160 fs/select.c:759
 __do_sys_pselect6 fs/select.c:784 [inline]
 __se_sys_pselect6 fs/select.c:769 [inline]
 __x64_sys_pselect6+0x12e/0x170 fs/select.c:769
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffffc900018a7a20 of 4 bytes by task 13718 on cpu 1:
 __pollwake fs/select.c:197 [inline]
 pollwake+0xe3/0x140 fs/select.c:217
 __wake_up_common+0x7b/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 __wake_up+0xe/0x10 kernel/sched/wait.c:142
 snd_seq_cell_free+0x24d/0x280 sound/core/seq/seq_memory.c:198
 snd_seq_dispatch_event+0xac/0x340 sound/core/seq/seq_clientmgr.c:914
 snd_seq_check_queue+0xeb/0x200 sound/core/seq/seq_queue.c:262
 snd_seq_enqueue_event+0x163/0x2b0 sound/core/seq/seq_queue.c:330
 snd_seq_client_enqueue_event.constprop.0+0x187/0x2a0 sound/core/seq/seq_clientmgr.c:974
 snd_seq_write+0x23f/0x4d0 sound/core/seq/seq_clientmgr.c:1093
 __vfs_write+0x67/0xc0 fs/read_write.c:494
 vfs_write fs/read_write.c:558 [inline]
 vfs_write+0x18a/0x390 fs/read_write.c:542
 ksys_write+0x17b/0x1b0 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x4c/0x60 fs/read_write.c:620
 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: 13718 Comm: syz-executor.0 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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