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BUG: KCSAN: data-race in snd_seq_check_queue / snd_seq_control_queue

read to 0xffff8880352eb424 of 1 bytes by interrupt on cpu 1:
 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
 xas_descend lib/xarray.c:203 [inline]
 xas_load+0x287/0x360 lib/xarray.c:240
 xa_load+0x76/0xe0 lib/xarray.c:1455
 page_cache_ra_unbounded+0x116/0x4c0 mm/readahead.c:199
 do_page_cache_ra mm/readahead.c:267 [inline]
 force_page_cache_ra+0x226/0x260 mm/readahead.c:298
 page_cache_sync_ra+0x194/0x1c0 mm/readahead.c:572
 page_cache_sync_readahead include/linux/pagemap.h:839 [inline]
 generic_file_buffered_read+0x38d/0x2110 mm/filemap.c:2227
 generic_file_read_iter+0x80/0x3d0 mm/filemap.c:2535
 blkdev_read_iter+0xb3/0xc0 fs/block_dev.c:1925
 call_read_iter include/linux/fs.h:1897 [inline]
 new_sync_read fs/read_write.c:415 [inline]
 vfs_read+0x552/0x5c0 fs/read_write.c:496
 ksys_read+0xce/0x180 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read fs/read_write.c:642 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:642
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read-write to 0xffff8880352eb424 of 1 bytes by task 1431 on cpu 0:
 queue_access_unlock sound/core/seq/seq_queue.c:370 [inline]
 snd_seq_control_queue+0x535/0x580 sound/core/seq/seq_queue.c:734
 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: 0 PID: 1431 Comm: syz-executor.0 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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