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BUG: KCSAN: data-race in snd_seq_check_queue / snd_seq_control_queue

write to 0xffff88808e348664 of 1 bytes by interrupt on cpu 1:
 snd_seq_check_queue+0x251/0x290 sound/core/seq/seq_queue.c:283
 snd_seq_timer_interrupt+0x228/0x240 sound/core/seq/seq_timer.c:158
 snd_timer_process_callbacks sound/core/timer.c:796 [inline]
 snd_timer_interrupt+0xa7c/0xb50 sound/core/timer.c:919
 snd_hrtimer_callback+0x13a/0x220 sound/core/hrtimer.c:50
 __run_hrtimer+0x154/0x4b0 kernel/time/hrtimer.c:1524
 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline]
 hrtimer_interrupt+0x37c/0xa40 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x280 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+0x80/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
 is_atomic kernel/kcsan/core.c:229 [inline]
 should_watch kernel/kcsan/core.c:257 [inline]
 check_access kernel/kcsan/core.c:603 [inline]
 __tsan_read8+0x11a/0x180 kernel/kcsan/core.c:801
 pte_val arch/x86/include/asm/paravirt.h:396 [inline]
 pte_pfn arch/x86/include/asm/pgtable.h:215 [inline]
 vm_normal_page+0x24/0x1d0 mm/memory.c:598
 zap_pte_range+0x2a9/0x1630 mm/memory.c:1255
 zap_pmd_range mm/memory.c:1386 [inline]
 zap_pud_range mm/memory.c:1415 [inline]
 zap_p4d_range mm/memory.c:1436 [inline]
 unmap_page_range+0x751/0x870 mm/memory.c:1457
 unmap_single_vma+0x157/0x210 mm/memory.c:1502
 unmap_vmas+0xc0/0x150 mm/memory.c:1534
 exit_mmap+0x1c7/0x3b0 mm/mmap.c:3183
 __mmput+0xa2/0x220 kernel/fork.c:1077
 mmput+0x38/0x40 kernel/fork.c:1098
 exit_mm+0x2c8/0x330 kernel/exit.c:483
 do_exit+0x40f/0x16c0 kernel/exit.c:793
 do_group_exit+0x17a/0x180 kernel/exit.c:903
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:914
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:912
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:912
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88808e348664 of 1 bytes by task 10959 on cpu 0:
 queue_access_lock sound/core/seq/seq_queue.c:345 [inline]
 snd_seq_control_queue+0xf5/0x550 sound/core/seq/seq_queue.c:727
 event_input_timer+0x1e/0x30 sound/core/seq/seq_system.c:103
 snd_seq_deliver_single_event+0x31b/0x4f0 sound/core/seq/seq_clientmgr.c:638
 snd_seq_deliver_event+0x192/0x4a0 sound/core/seq/seq_clientmgr.c:839
 snd_seq_dispatch_event+0x14c/0x270 sound/core/seq/seq_clientmgr.c:913
 snd_seq_check_queue+0xfe/0x290 sound/core/seq/seq_queue.c:264
 snd_seq_enqueue_event+0x275/0x2b0 sound/core/seq/seq_queue.c:333
 snd_seq_client_enqueue_event+0x206/0x2a0 sound/core/seq/seq_clientmgr.c:974
 snd_seq_write+0x435/0x550 sound/core/seq/seq_clientmgr.c:1093
 vfs_write+0x1df/0x6f0 fs/read_write.c:576
 ksys_write+0xce/0x180 fs/read_write.c:631
 __do_sys_write fs/read_write.c:643 [inline]
 __se_sys_write fs/read_write.c:640 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:640
 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: 10959 Comm: syz-executor.0 Not tainted 5.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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