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BUG: KCSAN: data-race in queue_access_lock / snd_seq_check_queue

read to 0xffff8880a6bb81e4 of 1 bytes by interrupt on cpu 0:
 snd_seq_check_queue+0x59/0x200 sound/core/seq/seq_queue.c:247
 snd_seq_timer_interrupt+0x243/0x280 sound/core/seq/seq_timer.c:158
 snd_timer_process_callbacks+0x1e4/0x220 sound/core/timer.c:750
 snd_timer_interrupt sound/core/timer.c:873 [inline]
 snd_timer_interrupt+0x483/0x930 sound/core/timer.c:794
 snd_hrtimer_callback+0x18f/0x260 sound/core/hrtimer.c:50
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1641
 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:829
 should_watch kernel/kcsan/core.c:206 [inline]
 check_access kernel/kcsan/core.c:458 [inline]
 __tsan_read4+0xb4/0x100 kernel/kcsan/core.c:588
 arch_atomic_read arch/x86/include/asm/atomic.h:31 [inline]
 atomic_read include/asm-generic/atomic-instrumented.h:41 [inline]
 lock_page_memcg mm/memcontrol.c:1981 [inline]
 lock_page_memcg+0x5b/0x110 mm/memcontrol.c:1956
 page_add_file_rmap+0x3b/0x480 mm/rmap.c:1204
 alloc_set_pte+0x46e/0xf50 mm/memory.c:3403
 filemap_map_pages+0x942/0x990 mm/filemap.c:2654
 do_fault_around mm/memory.c:3546 [inline]
 do_read_fault mm/memory.c:3580 [inline]
 do_fault mm/memory.c:3714 [inline]
 handle_pte_fault mm/memory.c:3945 [inline]
 __handle_mm_fault+0x2a92/0x2e00 mm/memory.c:4075
 handle_mm_fault+0x21b/0x530 mm/memory.c:4112
 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
 __do_page_fault+0x456/0x8d0 arch/x86/mm/fault.c:1506
 do_page_fault+0x38/0x194 arch/x86/mm/fault.c:1530
 page_fault+0x34/0x40 arch/x86/entry/entry_64.S:1203

write to 0xffff8880a6bb81e4 of 1 bytes by task 19812 on cpu 1:
 queue_access_lock+0x89/0xc0 sound/core/seq/seq_queue.c:356
 snd_seq_control_queue+0x77/0x350 sound/core/seq/seq_queue.c:719
 event_input_timer+0x2f/0x50 sound/core/seq/seq_system.c:103
 snd_seq_deliver_single_event.constprop.0+0x3e8/0x4d0 sound/core/seq/seq_clientmgr.c:638
 snd_seq_deliver_event+0x2e9/0x4c0 sound/core/seq/seq_clientmgr.c:839
 snd_seq_dispatch_event+0xa1/0x340 sound/core/seq/seq_clientmgr.c:913
 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/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19812 Comm: syz-executor.0 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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