===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 5.15.0-rc6-next-20211020-syzkaller #0 Not tainted ----------------------------------------------------- syz-executor.4/22644 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8b80a098 (tasklist_lock){.+.+}-{2:2}, at: send_sigio+0xab/0x380 fs/fcntl.c:810 and this task is already holding: ffff88801d1772b8 (&f->f_owner.lock){.-.-}-{2:2}, at: send_sigio+0x24/0x380 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 kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 snd_timer_notify sound/core/timer.c:1087 [inline] snd_timer_notify+0x10c/0x3d0 sound/core/timer.c:1074 snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline] snd_pcm_post_stop+0x195/0x1f0 sound/core/pcm_native.c:1453 snd_pcm_action_single sound/core/pcm_native.c:1229 [inline] snd_pcm_drain_done+0xdc/0x120 sound/core/pcm_native.c:1491 snd_pcm_update_state+0x43b/0x540 sound/core/pcm_lib.c:191 snd_pcm_update_hw_ptr0+0xa75/0x1a50 sound/core/pcm_lib.c:465 snd_pcm_period_elapsed_under_stream_lock+0x15a/0x230 sound/core/pcm_lib.c:1817 snd_pcm_period_elapsed+0x28/0x50 sound/core/pcm_lib.c:1849 dummy_hrtimer_callback+0x94/0x1b0 sound/drivers/dummy.c:377 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 __sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:515 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:410 [inline] batadv_nc_worker+0x10d/0xfa0 net/batman-adv/network-coding.c:721 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{2:2} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228 do_wait+0x284/0xce0 kernel/exit.c:1511 kernel_wait+0x9c/0x150 kernel/exit.c:1701 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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.4/22644: #0: ffffffff8bb835a0 (rcu_read_lock){....}-{1:2}, at: sock_def_readable+0x0/0x4e0 include/trace/events/sock.h:204 #1: ffffffff8bb835a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_unlock include/linux/rcupdate.h:723 [inline] #1: ffffffff8bb835a0 (rcu_read_lock){....}-{1:2}, at: sock_def_readable+0x2aa/0x4e0 net/core/sock.c:3139 #2: ffffffff8bb835a0 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x41/0x470 fs/fcntl.c:1033 #3: ffff88807774a600 (&new->fa_lock){.-.-}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1014 [inline] #3: ffff88807774a600 (&new->fa_lock){.-.-}-{2:2}, at: kill_fasync fs/fcntl.c:1035 [inline] #3: ffff88807774a600 (&new->fa_lock){.-.-}-{2:2}, at: kill_fasync+0x136/0x470 fs/fcntl.c:1028 #4: ffff88801d1772b8 (&f->f_owner.lock){.-.-}-{2:2}, at: send_sigio+0x24/0x380 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 kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 snd_timer_notify sound/core/timer.c:1087 [inline] snd_timer_notify+0x10c/0x3d0 sound/core/timer.c:1074 snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline] snd_pcm_post_stop+0x195/0x1f0 sound/core/pcm_native.c:1453 snd_pcm_action_single sound/core/pcm_native.c:1229 [inline] snd_pcm_drain_done+0xdc/0x120 sound/core/pcm_native.c:1491 snd_pcm_update_state+0x43b/0x540 sound/core/pcm_lib.c:191 snd_pcm_update_hw_ptr0+0xa75/0x1a50 sound/core/pcm_lib.c:465 snd_pcm_period_elapsed_under_stream_lock+0x15a/0x230 sound/core/pcm_lib.c:1817 snd_pcm_period_elapsed+0x28/0x50 sound/core/pcm_lib.c:1849 dummy_hrtimer_callback+0x94/0x1b0 sound/drivers/dummy.c:377 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 __sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:515 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:410 [inline] batadv_nc_worker+0x10d/0xfa0 net/batman-adv/network-coding.c:721 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 snd_timer_notify sound/core/timer.c:1087 [inline] snd_timer_notify+0x10c/0x3d0 sound/core/timer.c:1074 snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline] snd_pcm_post_stop+0x195/0x1f0 sound/core/pcm_native.c:1453 snd_pcm_action_single sound/core/pcm_native.c:1229 [inline] snd_pcm_action+0x143/0x170 sound/core/pcm_native.c:1310 snd_pcm_stop sound/core/pcm_native.c:1476 [inline] snd_pcm_drop+0x1ab/0x320 sound/core/pcm_native.c:2155 snd_pcm_kernel_ioctl+0x2af/0x310 sound/core/pcm_native.c:3382 snd_pcm_oss_sync+0x230/0x800 sound/core/oss/pcm_oss.c:1721 snd_pcm_oss_release+0x276/0x300 sound/core/oss/pcm_oss.c:2571 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 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+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] __key.12+0x0/0x40 -> (&new->fa_lock){.-.-}-{2:2} { IN-HARDIRQ-R at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x45/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x136/0x470 fs/fcntl.c:1028 perf_event_wakeup kernel/events/core.c:6434 [inline] perf_pending_event+0x432/0x560 kernel/events/core.c:6517 irq_work_single+0x120/0x270 kernel/irq_work.c:211 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:242 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x40/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 IN-SOFTIRQ-R at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x45/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x136/0x470 fs/fcntl.c:1028 perf_event_wakeup kernel/events/core.c:6434 [inline] perf_pending_event+0x432/0x560 kernel/events/core.c:6517 irq_work_single+0x120/0x270 kernel/irq_work.c:211 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:242 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x8e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 ffs arch/x86/include/asm/bitops.h:297 [inline] __do_softirq+0x196/0x9c2 kernel/softirq.c:546 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x45/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316 fasync_remove_entry+0xb6/0x1f0 fs/fcntl.c:891 fasync_helper+0x9e/0xb0 fs/fcntl.c:994 __fput+0x846/0x9f0 fs/file_table.c:277 task_work_run+0xdd/0x1a0 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+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x136/0x470 fs/fcntl.c:1028 snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387 snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516 snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_start sound/core/timer.c:690 [inline] snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985 __snd_timer_user_ioctl.isra.0+0xda8/0x2490 sound/core/timer.c:2108 snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] __key.0+0x0/0x40 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1014 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x136/0x470 fs/fcntl.c:1028 snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387 snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516 snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_start sound/core/timer.c:690 [inline] snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985 __snd_timer_user_ioctl.isra.0+0xda8/0x2490 sound/core/timer.c:2108 snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> (&f->f_owner.lock){.-.-}-{2:2} { IN-HARDIRQ-R at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x45/0x90 kernel/locking/spinlock.c:236 send_sigio+0x24/0x380 fs/fcntl.c:796 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x1f8/0x470 fs/fcntl.c:1028 perf_event_wakeup kernel/events/core.c:6434 [inline] perf_pending_event+0x432/0x560 kernel/events/core.c:6517 irq_work_single+0x120/0x270 kernel/irq_work.c:211 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:242 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x40/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 IN-SOFTIRQ-R at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x45/0x90 kernel/locking/spinlock.c:236 send_sigio+0x24/0x380 fs/fcntl.c:796 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x1f8/0x470 fs/fcntl.c:1028 perf_event_wakeup kernel/events/core.c:6434 [inline] perf_pending_event+0x432/0x560 kernel/events/core.c:6517 irq_work_single+0x120/0x270 kernel/irq_work.c:211 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:242 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x8e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 ffs arch/x86/include/asm/bitops.h:297 [inline] __do_softirq+0x196/0x9c2 kernel/softirq.c:546 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x45/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316 f_modown+0x2a/0x390 fs/fcntl.c:91 __f_setown fs/fcntl.c:110 [inline] f_setown+0xd7/0x230 fs/fcntl.c:138 sock_ioctl+0x37e/0x640 net/socket.c:1178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock_irq include/linux/rwlock_api_smp.h:169 [inline] _raw_read_lock_irq+0x63/0x80 kernel/locking/spinlock.c:244 f_getown+0x23/0x2a0 fs/fcntl.c:154 do_fcntl+0xbd8/0x1210 fs/fcntl.c:389 __do_sys_fcntl fs/fcntl.c:472 [inline] __se_sys_fcntl fs/fcntl.c:457 [inline] __x64_sys_fcntl+0x165/0x1e0 fs/fcntl.c:457 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] __key.5+0x0/0x40 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline] _raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236 send_sigio+0x24/0x380 fs/fcntl.c:796 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x1f8/0x470 fs/fcntl.c:1028 snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387 snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516 snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_start sound/core/timer.c:690 [inline] snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985 __snd_timer_user_ioctl.isra.0+0xda8/0x2490 sound/core/timer.c:2108 snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 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 kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228 do_wait+0x284/0xce0 kernel/exit.c:1511 kernel_wait+0x9c/0x150 kernel/exit.c:1701 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 SOFTIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228 do_wait+0x284/0xce0 kernel/exit.c:1511 kernel_wait+0x9c/0x150 kernel/exit.c:1701 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316 copy_process+0x36c0/0x75a0 kernel/fork.c:2361 kernel_clone+0xe7/0xab0 kernel/fork.c:2632 kernel_thread+0xb5/0xf0 kernel/fork.c:2684 rest_init+0x23/0x3e0 init/main.c:700 start_kernel+0x47a/0x49b init/main.c:1149 secondary_startup_64_no_verify+0xb0/0xbb INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228 do_wait+0x284/0xce0 kernel/exit.c:1511 kernel_wait+0x9c/0x150 kernel/exit.c:1701 call_usermodehelper_exec_sync kernel/umh.c:139 [inline] call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228 send_sigio+0xab/0x380 fs/fcntl.c:810 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x1f8/0x470 fs/fcntl.c:1028 sock_wake_async+0xd2/0x160 net/socket.c:1368 sk_wake_async include/net/sock.h:2390 [inline] sk_wake_async include/net/sock.h:2386 [inline] sock_def_readable+0x349/0x4e0 net/core/sock.c:3138 unix_dgram_sendmsg+0xfa7/0x1950 net/unix/af_unix.c:1941 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x331/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmmsg+0x195/0x470 net/socket.c:2549 __do_sys_sendmmsg net/socket.c:2578 [inline] __se_sys_sendmmsg net/socket.c:2575 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2575 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae stack backtrace: CPU: 1 PID: 22644 Comm: syz-executor.4 Not tainted 5.15.0-rc6-next-20211020-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+0xcd/0x134 lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2577 [inline] check_irq_usage.cold+0x4c1/0x6b0 kernel/locking/lockdep.c:2816 check_prev_add kernel/locking/lockdep.c:3067 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain kernel/locking/lockdep.c:3801 [inline] __lock_acquire+0x2a1f/0x54a0 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228 send_sigio+0xab/0x380 fs/fcntl.c:810 kill_fasync_rcu fs/fcntl.c:1021 [inline] kill_fasync fs/fcntl.c:1035 [inline] kill_fasync+0x1f8/0x470 fs/fcntl.c:1028 sock_wake_async+0xd2/0x160 net/socket.c:1368 sk_wake_async include/net/sock.h:2390 [inline] sk_wake_async include/net/sock.h:2386 [inline] sock_def_readable+0x349/0x4e0 net/core/sock.c:3138 unix_dgram_sendmsg+0xfa7/0x1950 net/unix/af_unix.c:1941 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x331/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmmsg+0x195/0x470 net/socket.c:2549 __do_sys_sendmmsg net/socket.c:2578 [inline] __se_sys_sendmmsg net/socket.c:2575 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2575 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fecc8b56a39 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:00007fecc60cc188 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fecc8c59f60 RCX: 00007fecc8b56a39 RDX: 0307017fdb7a66cb RSI: 0000000020002dc0 RDI: 0000000000000006 RBP: 00007fecc8bb0c5f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000003ec0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd5f6d352f R14: 00007fecc60cc300 R15: 0000000000022000