===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 5.15.0-rc5-syzkaller #0 Not tainted ----------------------------------------------------- syz-executor.1/9229 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8c60a058 (tasklist_lock){.+.+}-{2:2}, at: send_sigio+0xbe/0x300 fs/fcntl.c:810 and this task is already holding: ffff88807d9657b8 (&f->f_owner.lock){...-}-{2:2}, at: send_sigio+0x2f/0x300 fs/fcntl.c:796 which would create a new lock dependency: (&f->f_owner.lock){...-}-{2:2} -> (tasklist_lock){.+.+}-{2:2} but this new dependency connects a SOFTIRQ-irq-safe lock: (&timer->lock){..-.}-{2:2} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 snd_timer_notify+0x105/0x3e0 sound/core/timer.c:1087 snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline] snd_pcm_post_stop sound/core/pcm_native.c:1453 [inline] snd_pcm_action_single sound/core/pcm_native.c:1229 [inline] snd_pcm_drain_done+0x2fd/0x400 sound/core/pcm_native.c:1491 snd_pcm_update_state+0x342/0x440 sound/core/pcm_lib.c:190 snd_pcm_update_hw_ptr0+0xfff/0x1980 sound/core/pcm_lib.c:464 snd_pcm_period_elapsed_under_stream_lock sound/core/pcm_lib.c:1816 [inline] snd_pcm_period_elapsed+0xfb/0x210 sound/core/pcm_lib.c:1848 dummy_hrtimer_callback+0x87/0x190 sound/drivers/dummy.c:377 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x1b7/0x5d0 kernel/time/hrtimer.c:1766 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 do_softirq+0x161/0x240 kernel/softirq.c:459 __local_bh_enable_ip+0x1b0/0x1f0 kernel/softirq.c:383 spin_unlock_bh include/linux/spinlock.h:408 [inline] batadv_nc_purge_paths+0x35f/0x3f0 net/batman-adv/network-coding.c:473 batadv_nc_worker+0x2da/0x5b0 net/batman-adv/network-coding.c:722 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{2:2} ... which became SOFTIRQ-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:1504 kernel_wait+0xe4/0x230 kernel/exit.c:1694 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:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &timer->lock --> &f->f_owner.lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&timer->lock); lock(&f->f_owner.lock); lock(&timer->lock); *** DEADLOCK *** 5 locks held by syz-executor.1/9229: #0: ffffffff8c91c8c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #1: ffffffff8c91c8c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #2: ffffffff8c91c8c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:266 #3: ffff888089a496a8 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1014 [inline] #3: ffff888089a496a8 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x13b/0x430 fs/fcntl.c:1035 #4: ffff88807d9657b8 (&f->f_owner.lock){...-}-{2:2}, at: send_sigio+0x2f/0x300 fs/fcntl.c:796 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&timer->lock){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 snd_timer_notify+0x105/0x3e0 sound/core/timer.c:1087 snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline] snd_pcm_post_stop sound/core/pcm_native.c:1453 [inline] snd_pcm_action_single sound/core/pcm_native.c:1229 [inline] snd_pcm_drain_done+0x2fd/0x400 sound/core/pcm_native.c:1491 snd_pcm_update_state+0x342/0x440 sound/core/pcm_lib.c:190 snd_pcm_update_hw_ptr0+0xfff/0x1980 sound/core/pcm_lib.c:464 snd_pcm_period_elapsed_under_stream_lock sound/core/pcm_lib.c:1816 [inline] snd_pcm_period_elapsed+0xfb/0x210 sound/core/pcm_lib.c:1848 dummy_hrtimer_callback+0x87/0x190 sound/drivers/dummy.c:377 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x1b7/0x5d0 kernel/time/hrtimer.c:1766 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 do_softirq+0x161/0x240 kernel/softirq.c:459 __local_bh_enable_ip+0x1b0/0x1f0 kernel/softirq.c:383 spin_unlock_bh include/linux/spinlock.h:408 [inline] batadv_nc_purge_paths+0x35f/0x3f0 net/batman-adv/network-coding.c:473 batadv_nc_worker+0x2da/0x5b0 net/batman-adv/network-coding.c:722 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 INITIAL USE at: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:388 [inline] snd_pcm_detach_substream+0x14b/0x280 sound/core/pcm.c:995 snd_pcm_release+0xbd/0x160 sound/core/pcm_native.c:2823 __fput+0x3fe/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 -> (&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:196 [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+0x720/0x870 fs/file_table.c:277 task_work_run+0x146/0x1c0 kernel/task_work.c:164 get_signal+0x2014/0x20c0 kernel/signal.c:2641 arch_do_signal_or_restart+0x9c/0x730 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x191/0x220 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:716 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2369 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+0x3fe/0x870 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 get_signal+0x2014/0x20c0 kernel/signal.c:2641 arch_do_signal_or_restart+0x9c/0x730 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x191/0x220 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+0xe8b/0x60a0 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 -> (&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:3090 tcp_check_urg net/ipv4/tcp_input.c:5550 [inline] tcp_urg+0x2b6/0xb40 net/ipv4/tcp_input.c:5591 tcp_rcv_established+0x9ec/0x22b0 net/ipv4/tcp_input.c:5925 tcp_v4_do_rcv+0x3a1/0x880 net/ipv4/tcp_ipv4.c:1694 tcp_v4_rcv+0x3aa1/0x4880 net/ipv4/tcp_ipv4.c:2087 ip_protocol_deliver_rcu+0x1ed/0x3b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x316/0x490 net/ipv4/ip_input.c:252 __netif_receive_skb_one_core net/core/dev.c:5436 [inline] __netif_receive_skb+0x1d1/0x500 net/core/dev.c:5550 process_backlog+0x518/0x9a0 net/core/dev.c:6427 __napi_poll+0xba/0x4f0 net/core/dev.c:6986 napi_poll net/core/dev.c:7053 [inline] net_rx_action+0x61c/0xf30 net/core/dev.c:7140 __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+0x453/0x480 kernel/kthread.c:319 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:196 [inline] _raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316 f_modown+0x38/0x340 fs/fcntl.c:91 fcntl_dirnotify+0x5d3/0xae0 fs/notify/dnotify/dnotify.c:351 do_fcntl+0x5ec/0x1560 fs/fcntl.c:422 __do_sys_fcntl fs/fcntl.c:472 [inline] __se_sys_fcntl+0xd8/0x1b0 fs/fcntl.c:457 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:3090 tcp_check_urg net/ipv4/tcp_input.c:5550 [inline] tcp_urg+0x2b6/0xb40 net/ipv4/tcp_input.c:5591 tcp_rcv_established+0x9ec/0x22b0 net/ipv4/tcp_input.c:5925 tcp_v4_do_rcv+0x3a1/0x880 net/ipv4/tcp_ipv4.c:1694 sk_backlog_rcv include/net/sock.h:1027 [inline] __release_sock+0x1d8/0x4c0 net/core/sock.c:2686 release_sock+0x5d/0x1c0 net/core/sock.c:3218 tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1462 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] __sys_sendto+0x560/0x720 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2044 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 } ... 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:716 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2369 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+0x3fe/0x870 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 get_signal+0x2014/0x20c0 kernel/signal.c:2641 arch_do_signal_or_restart+0x9c/0x730 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x191/0x220 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 the dependencies between the lock to be acquired and SOFTIRQ-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:1504 kernel_wait+0xe4/0x230 kernel/exit.c:1694 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:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 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:1504 kernel_wait+0xe4/0x230 kernel/exit.c:1694 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:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 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:196 [inline] _raw_write_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:316 copy_process+0x34b4/0x5c90 kernel/fork.c:2313 kernel_clone+0x230/0x7d0 kernel/fork.c:2584 kernel_thread+0x155/0x1d0 kernel/fork.c:2636 rest_init+0x21/0x2e0 init/main.c:699 start_kernel+0x4bf/0x56e init/main.c:1142 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:1504 kernel_wait+0xe4/0x230 kernel/exit.c:1694 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:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 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:716 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2369 sock_def_readable+0x152/0x200 net/core/sock.c:3056 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+0x57e/0x800 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 stack backtrace: CPU: 1 PID: 9229 Comm: syz-executor.1 Not tainted 5.15.0-rc5-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 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:716 [inline] sk_wake_async+0x12e/0x200 include/net/sock.h:2369 sock_def_readable+0x152/0x200 net/core/sock.c:3056 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+0x57e/0x800 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 RIP: 0033:0x7f38ef073a39 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:00007f38ec5e9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f38ef176f60 RCX: 00007f38ef073a39 RDX: 0307017fdb7a66cb RSI: 0000000020002dc0 RDI: 0000000000000004 RBP: 00007f38ef0cdc5f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000003ec0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe339c367f R14: 00007f38ec5e9300 R15: 0000000000022000