======================================================== WARNING: possible irq lock inversion dependency detected 5.15.0-rc3-syzkaller #0 Not tainted -------------------------------------------------------- kworker/u4:13/12001 just changed the state of lock: ffff888147b80108 (&group->lock){..-.}-{2:2}, at: snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1847 but this lock took another, SOFTIRQ-READ-unsafe lock in the past: (tasklist_lock){.+.+}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Chain exists of: &group->lock --> &timer->lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&group->lock); lock(&timer->lock); lock(&group->lock); *** DEADLOCK *** 3 locks held by kworker/u4:13/12001: #0: ffff888148451938 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc90016f2fd20 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffc90000dc0ca0 ((&dpcm->timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline] #2: ffffc90000dc0ca0 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xbd/0x210 kernel/time/timer.c:1411 the shortest dependencies between 2nd lock and 1st 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+0x34b4/0x5c80 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:698 start_kernel+0x4bf/0x56e init/main.c:1141 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 dnotify_handle_event+0x136/0x450 fs/notify/dnotify/dnotify.c:97 fsnotify+0x9e5/0x12e0 fs/notify/fsnotify.c:541 fsnotify_name include/linux/fsnotify.h:36 [inline] fsnotify_dirent include/linux/fsnotify.h:42 [inline] fsnotify_create include/linux/fsnotify.h:198 [inline] vfs_mknod+0x627/0x710 fs/namei.c:3765 unix_bind_bsd net/unix/af_unix.c:1058 [inline] unix_bind+0x5cb/0xd50 net/unix/af_unix.c:1146 __sys_bind+0x314/0x400 net/socket.c:1693 __do_sys_bind net/socket.c:1704 [inline] __se_sys_bind net/socket.c:1702 [inline] __x64_sys_bind+0x76/0x80 net/socket.c:1702 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} { 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 generic_add_lease fs/locks.c:1845 [inline] generic_setlease+0xbde/0x1330 fs/locks.c:1924 vfs_setlease fs/locks.c:2014 [inline] do_fcntl_add_lease fs/locks.c:2035 [inline] fcntl_setlease+0x656/0x770 fs/locks.c:2057 do_fcntl+0x10a/0x1560 fs/fcntl.c:419 __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_sigio+0x2f/0x300 fs/fcntl.c:796 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync+0x1e4/0x430 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 } ... 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 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 -> (&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 __fput+0x720/0x870 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 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 } ... 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 -> (&timer->lock){....}-{2:2} { INITIAL USE 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_action sound/core/pcm_native.c:1310 [inline] snd_pcm_stop+0x3b8/0x4c0 sound/core/pcm_native.c:1476 snd_pcm_drop+0x16d/0x290 sound/core/pcm_native.c:2155 snd_pcm_oss_sync+0x4f4/0xee0 sound/core/oss/pcm_oss.c:1721 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2571 __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 ... acquired 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_action sound/core/pcm_native.c:1310 [inline] snd_pcm_stop+0x3b8/0x4c0 sound/core/pcm_native.c:1476 snd_pcm_drop+0x16d/0x290 sound/core/pcm_native.c:2155 snd_pcm_oss_sync+0x4f4/0xee0 sound/core/oss/pcm_oss.c:1721 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2571 __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 -> (&group->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_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1847 call_timer_fn+0xf6/0x210 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x71a/0x910 kernel/time/timer.c:1734 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1747 __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+0x31e/0x5b0 net/batman-adv/network-coding.c:724 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_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] snd_pcm_hw_params+0xca/0x1740 sound/core/pcm_native.c:686 snd_pcm_oss_change_params_locked+0x2453/0x43e0 sound/core/oss/pcm_oss.c:947 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1091 [inline] snd_pcm_oss_make_ready sound/core/oss/pcm_oss.c:1150 [inline] snd_pcm_oss_sync+0x37c/0xee0 sound/core/oss/pcm_oss.c:1717 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2571 __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_pcm_group_init.__key+0x0/0x40 ... acquired at: __lock_acquire+0xc36/0x2b00 kernel/locking/lockdep.c:4969 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_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1847 call_timer_fn+0xf6/0x210 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x71a/0x910 kernel/time/timer.c:1734 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1747 __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+0x31e/0x5b0 net/batman-adv/network-coding.c:724 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 stack backtrace: CPU: 1 PID: 12001 Comm: kworker/u4:13 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 print_irq_inversion_bug+0x87f/0xb60 kernel/locking/lockdep.c:4000 mark_lock_irq kernel/locking/lockdep.c:4163 [inline] mark_lock+0x10bd/0x1e00 kernel/locking/lockdep.c:4593 __lock_acquire+0xc36/0x2b00 kernel/locking/lockdep.c:4969 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_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1847 call_timer_fn+0xf6/0x210 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x71a/0x910 kernel/time/timer.c:1734 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1747 __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+0x31e/0x5b0 net/batman-adv/network-coding.c:724 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