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BUG: KCSAN: data-race in snd_seq_check_queue / snd_seq_control_queue

write to 0xffff88811eccca24 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_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [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
 arch_local_irq_enable arch/x86/include/asm/paravirt.h:780 [inline]
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
 _raw_spin_unlock_irq+0x41/0x70 kernel/locking/spinlock.c:199
 finish_lock_switch kernel/sched/core.c:3517 [inline]
 finish_task_switch+0x8b/0x270 kernel/sched/core.c:3617
 context_switch kernel/sched/core.c:3781 [inline]
 __schedule+0x3c5/0x590 kernel/sched/core.c:4527
 schedule+0x91/0xd0 kernel/sched/core.c:4602
 schedule_timeout+0x46/0x2c0 kernel/time/timer.c:1855
 __skb_wait_for_more_packets+0x1b9/0x2a0 net/core/datagram.c:122
 __skb_recv_udp+0x6be/0x7d0 net/ipv4/udp.c:1771
 udpv6_recvmsg+0x1f2/0xc50 net/ipv6/udp.c:343
 inet6_recvmsg+0xa3/0x210 net/ipv6/af_inet6.c:654
 ____sys_recvmsg+0x15a/0x2e0 include/linux/uio.h:234
 ___sys_recvmsg net/socket.c:2618 [inline]
 do_recvmmsg+0x35c/0xa30 net/socket.c:2716
 __sys_recvmmsg net/socket.c:2795 [inline]
 __do_sys_recvmmsg net/socket.c:2818 [inline]
 __se_sys_recvmmsg net/socket.c:2811 [inline]
 __x64_sys_recvmmsg+0xcc/0x150 net/socket.c:2811
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88811eccca24 of 1 bytes by task 12358 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: 12358 Comm: syz-executor.5 Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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