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BUG: KCSAN: data-race in snd_seq_check_queue / snd_seq_control_queue

read to 0xffff8880390d3064 of 1 bytes by interrupt on cpu 0:
 snd_seq_check_queue+0x51/0x2a0 sound/core/seq/seq_queue.c:249
 snd_seq_timer_interrupt+0x20e/0x220 sound/core/seq/seq_timer.c:158
 snd_timer_process_callbacks sound/core/timer.c:796 [inline]
 snd_timer_interrupt+0xa1c/0xae0 sound/core/timer.c:919
 snd_hrtimer_callback+0x139/0x200 sound/core/hrtimer.c:50
 __run_hrtimer+0x133/0x420 kernel/time/hrtimer.c:1519
 __hrtimer_run_queues kernel/time/hrtimer.c:1583 [inline]
 hrtimer_interrupt+0x36e/0xa10 kernel/time/hrtimer.c:1645
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x6f/0x200 arch/x86/kernel/apic/apic.c:1097
 asm_call_irq_on_stack+0xf/0x20
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0x52/0x90 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
 native_restore_fl arch/x86/include/asm/irqflags.h:41 [inline]
 arch_local_irq_restore arch/x86/include/asm/irqflags.h:84 [inline]
 kcsan_setup_watchpoint+0x1ec/0x4d0 kernel/kcsan/core.c:591
 link_path_walk+0x354/0x710 fs/namei.c:2156
 path_lookupat+0x7b/0x550 fs/namei.c:2333
 filename_lookup+0xf2/0x380 fs/namei.c:2367
 user_path_at_empty+0x3b/0x50 fs/namei.c:2647
 do_readlinkat+0x87/0x200 fs/stat.c:407
 __do_sys_readlinkat fs/stat.c:434 [inline]
 __se_sys_readlinkat fs/stat.c:431 [inline]
 __x64_sys_readlinkat+0x4f/0x60 fs/stat.c:431
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880390d3064 of 1 bytes by task 11380 on cpu 1:
 queue_access_lock sound/core/seq/seq_queue.c:359 [inline]
 snd_seq_control_queue+0x189/0x580 sound/core/seq/seq_queue.c:727
 event_input_timer+0x1e/0x30 sound/core/seq/seq_system.c:103
 snd_seq_deliver_single_event+0x2f5/0x4b0 sound/core/seq/seq_clientmgr.c:638
 snd_seq_deliver_event+0x195/0x490 sound/core/seq/seq_clientmgr.c:839
 snd_seq_dispatch_event+0x12e/0x230 sound/core/seq/seq_clientmgr.c:913
 snd_seq_check_queue+0x10e/0x2a0 sound/core/seq/seq_queue.c:264
 snd_seq_enqueue_event+0x24c/0x290 sound/core/seq/seq_queue.c:333
 snd_seq_client_enqueue_event+0x206/0x2a0 sound/core/seq/seq_clientmgr.c:974
 snd_seq_write+0x425/0x530 sound/core/seq/seq_clientmgr.c:1093
 vfs_write+0x21a/0x7c0 fs/read_write.c:603
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11380 Comm: syz-executor.1 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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