===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 5.15.0-syzkaller #0 Not tainted ----------------------------------------------------- syz-executor.1/20196 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff888056565360 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1014 [inline] ffff888056565360 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x13b/0x430 fs/fcntl.c:1035 and this task is already holding: ffff8880217ef948 (&timer->lock){-.-.}-{2:2}, at: snd_timer_start1+0x5b/0x640 sound/core/timer.c:541 which would create a new lock dependency: (&timer->lock){-.-.}-{2:2} -> (&new->fa_lock){....}-{2:2} but this new dependency connects a HARDIRQ-irq-safe lock: (&timer->lock){-.-.}-{2:2} ... which became HARDIRQ-irq-safe at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] snd_hrtimer_callback+0x51/0x360 sound/core/hrtimer.c:38 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 to a HARDIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{2:2} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228 do_wait+0x224/0x9d0 kernel/exit.c:1505 kernel_wait+0xe4/0x230 kernel/exit.c:1695 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &timer->lock --> &new->fa_lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&timer->lock); lock(&new->fa_lock); lock(&timer->lock); *** DEADLOCK *** 3 locks held by syz-executor.1/20196: #0: ffff88801a750968 (&tu->ioctl_lock){+.+.}-{3:3}, at: snd_timer_user_ioctl+0x4d/0x80 sound/core/timer.c:2128 #1: ffff8880217ef948 (&timer->lock){-.-.}-{2:2}, at: snd_timer_start1+0x5b/0x640 sound/core/timer.c:541 #2: ffffffff8cb1d840 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:267 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&timer->lock){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] snd_hrtimer_callback+0x51/0x360 sound/core/hrtimer.c:38 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 IN-SOFTIRQ-W at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] snd_hrtimer_callback+0x51/0x360 sound/core/hrtimer.c:38 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 rcu_report_qs_rsp+0xab/0x1a0 kernel/rcu/tree.c:2153 rcu_report_qs_rdp kernel/rcu/tree.c:2312 [inline] rcu_check_quiescent_state kernel/rcu/tree.c:2349 [inline] rcu_core+0x11d5/0x1610 kernel/rcu/tree.c:2725 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x43/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 INITIAL USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:375 [inline] snd_timer_close_locked+0x5c/0x8e0 sound/core/timer.c:396 snd_timer_close+0xaa/0x120 sound/core/timer.c:463 snd_seq_timer_close+0x9b/0xd0 sound/core/seq/seq_timer.c:326 queue_delete sound/core/seq/seq_queue.c:134 [inline] snd_seq_queue_delete+0x8b/0xf0 sound/core/seq/seq_queue.c:196 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:377 [inline] snd_seq_oss_release+0x1d6/0x310 sound/core/seq/oss/seq_oss_init.c:422 odev_release+0x52/0x70 sound/core/seq/oss/seq_oss.c:144 __fput+0x3fc/0x870 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] snd_timer_new.__key+0x0/0x40 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{2:2} { HARDIRQ-ON-R at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228 do_wait+0x224/0x9d0 kernel/exit.c:1505 kernel_wait+0xe4/0x230 kernel/exit.c:1695 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 SOFTIRQ-ON-R at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228 do_wait+0x224/0x9d0 kernel/exit.c:1505 kernel_wait+0xe4/0x230 kernel/exit.c:1695 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 INITIAL USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline] _raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316 copy_process+0x34b4/0x5ca0 kernel/fork.c:2312 kernel_clone+0x22a/0x7e0 kernel/fork.c:2583 kernel_thread+0x155/0x1d0 kernel/fork.c:2635 rest_init+0x21/0x2e0 init/main.c:690 start_kernel+0x4bf/0x56e init/main.c:1133 secondary_startup_64_no_verify+0xb1/0xbb INITIAL READ USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228 do_wait+0x224/0x9d0 kernel/exit.c:1505 kernel_wait+0xe4/0x230 kernel/exit.c:1695 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xb4/0x220 kernel/umh.c:166 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:228 send_sigio+0xbe/0x300 fs/fcntl.c:810 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync+0x1e4/0x430 fs/fcntl.c:1035 sock_wake_async+0x133/0x150 rcu_read_unlock include/linux/rcupdate.h:717 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2401 sock_def_readable+0x152/0x200 net/core/sock.c:3138 unix_dgram_sendmsg+0x19cc/0x2a50 net/unix/af_unix.c:1941 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] ____sys_sendmsg+0x5b9/0x910 net/socket.c:2409 ___sys_sendmsg net/socket.c:2463 [inline] __sys_sendmmsg+0x3ba/0x750 net/socket.c:2549 __do_sys_sendmmsg net/socket.c:2578 [inline] __se_sys_sendmmsg net/socket.c:2575 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2575 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> (&f->f_owner.lock){...-}-{2:2} { IN-SOFTIRQ-R at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236 send_sigurg+0x25/0x360 fs/fcntl.c:835 sk_send_sigurg+0x6a/0xb0 net/core/sock.c:3172 tcp_check_urg net/ipv4/tcp_input.c:5567 [inline] tcp_urg+0x2b6/0xb40 net/ipv4/tcp_input.c:5608 tcp_rcv_established+0x9ec/0x22b0 net/ipv4/tcp_input.c:5942 tcp_v6_do_rcv+0x4ed/0x1370 net/ipv6/tcp_ipv6.c:1522 tcp_v6_rcv+0x357f/0x43e0 net/ipv6/tcp_ipv6.c:1765 ip6_protocol_deliver_rcu+0x9a5/0x1310 net/ipv6/ip6_input.c:422 ip6_input_finish net/ipv6/ip6_input.c:463 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip6_input+0x10b/0x190 net/ipv6/ip6_input.c:472 __netif_receive_skb_one_core net/core/dev.c:5462 [inline] __netif_receive_skb+0x1d1/0x500 net/core/dev.c:5576 process_backlog+0x518/0x9a0 net/core/dev.c:6452 __napi_poll+0xbd/0x520 net/core/dev.c:7017 napi_poll net/core/dev.c:7084 [inline] net_rx_action+0x61c/0xf30 net/core/dev.c:7171 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:920 smpboot_thread_fn+0x533/0x9d0 kernel/smpboot.c:164 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 INITIAL USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline] _raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316 f_modown+0x38/0x340 fs/fcntl.c:91 __f_setown fs/fcntl.c:110 [inline] f_setown+0x113/0x1a0 fs/fcntl.c:138 sock_ioctl+0x3d5/0x770 net/socket.c:1178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236 send_sigurg+0x25/0x360 fs/fcntl.c:835 sk_send_sigurg+0x6a/0xb0 net/core/sock.c:3172 tcp_check_urg net/ipv4/tcp_input.c:5567 [inline] tcp_urg+0x2b6/0xb40 net/ipv4/tcp_input.c:5608 tcp_rcv_established+0x9ec/0x22b0 net/ipv4/tcp_input.c:5942 tcp_v6_do_rcv+0x4ed/0x1370 net/ipv6/tcp_ipv6.c:1522 tcp_v6_rcv+0x357f/0x43e0 net/ipv6/tcp_ipv6.c:1765 ip6_protocol_deliver_rcu+0x9a5/0x1310 net/ipv6/ip6_input.c:422 ip6_input_finish net/ipv6/ip6_input.c:463 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip6_input+0x10b/0x190 net/ipv6/ip6_input.c:472 __netif_receive_skb_one_core net/core/dev.c:5462 [inline] __netif_receive_skb+0x1d1/0x500 net/core/dev.c:5576 process_backlog+0x518/0x9a0 net/core/dev.c:6452 __napi_poll+0xbd/0x520 net/core/dev.c:7017 napi_poll net/core/dev.c:7084 [inline] net_rx_action+0x61c/0xf30 net/core/dev.c:7171 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:920 smpboot_thread_fn+0x533/0x9d0 kernel/smpboot.c:164 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 } ... key at: [] __alloc_file.__key+0x0/0x10 ... acquired at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236 send_sigio+0x2f/0x300 fs/fcntl.c:796 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync+0x1e4/0x430 fs/fcntl.c:1035 sock_wake_async+0x133/0x150 rcu_read_unlock include/linux/rcupdate.h:717 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2401 unix_release_sock+0x491/0xa00 net/unix/af_unix.c:570 unix_release+0x88/0xc0 net/unix/af_unix.c:949 __sock_release net/socket.c:649 [inline] sock_close+0xd8/0x260 net/socket.c:1314 __fput+0x3fc/0x870 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae -> (&new->fa_lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline] _raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316 fasync_remove_entry+0xff/0x1d0 fs/fcntl.c:891 sock_fasync+0x86/0xf0 net/socket.c:1339 __fput+0x71e/0x870 fs/file_table.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync+0x13b/0x430 fs/fcntl.c:1035 sock_wake_async+0x133/0x150 rcu_read_unlock include/linux/rcupdate.h:717 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2401 unix_release_sock+0x491/0xa00 net/unix/af_unix.c:570 unix_release+0x88/0xc0 net/unix/af_unix.c:949 __sock_release net/socket.c:649 [inline] sock_close+0xd8/0x260 net/socket.c:1314 __fput+0x3fc/0x870 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] fasync_insert_entry.__key+0x0/0x40 ... acquired at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync+0x13b/0x430 fs/fcntl.c:1035 snd_timer_user_ccallback+0x370/0x540 sound/core/timer.c:1387 snd_timer_notify1+0x1ad/0x350 sound/core/timer.c:516 snd_timer_start1+0x53d/0x640 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_user_start sound/core/timer.c:1985 [inline] __snd_timer_user_ioctl+0xb56/0x5920 sound/core/timer.c:2108 snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae stack backtrace: CPU: 0 PID: 20196 Comm: syz-executor.1 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2565 [inline] check_irq_usage kernel/locking/lockdep.c:2804 [inline] check_prev_add kernel/locking/lockdep.c:3055 [inline] check_prevs_add kernel/locking/lockdep.c:3174 [inline] validate_chain+0x6f4c/0x8240 kernel/locking/lockdep.c:3789 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5015 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0xd9/0x120 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync+0x13b/0x430 fs/fcntl.c:1035 snd_timer_user_ccallback+0x370/0x540 sound/core/timer.c:1387 snd_timer_notify1+0x1ad/0x350 sound/core/timer.c:516 snd_timer_start1+0x53d/0x640 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_user_start sound/core/timer.c:1985 [inline] __snd_timer_user_ioctl+0xb56/0x5920 sound/core/timer.c:2108 snd_timer_user_ioctl+0x5d/0x80 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9f9ffdaae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9f9d50e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9fa00ee0e0 RCX: 00007f9f9ffdaae9 RDX: 0000000000000000 RSI: 00000000000054a0 RDI: 0000000000000003 RBP: 00007f9fa0034f25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff4507c3cf R14: 00007f9f9d50e300 R15: 0000000000022000