===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 5.15.0-syzkaller #0 Not tainted ----------------------------------------------------- syz-executor.0/5873 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8b60a098 (tasklist_lock){.+.+}-{2:2}, at: send_sigio+0xab/0x380 fs/fcntl.c:810 and this task is already holding: ffff888021f032b8 (&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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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_interrupt.part.0+0x34/0xcf0 sound/core/timer.c:857 snd_timer_interrupt sound/core/timer.c:1155 [inline] snd_timer_s_function+0x14b/0x200 sound/core/timer.c:1155 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 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 get_current arch/x86/include/asm/current.h:15 [inline] finish_task_switch.isra.0+0x323/0xb80 kernel/sched/core.c:4849 context_switch kernel/sched/core.c:4972 [inline] __schedule+0xaa2/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 freezable_schedule include/linux/freezer.h:172 [inline] do_nanosleep+0x24e/0x690 kernel/time/hrtimer.c:2044 hrtimer_nanosleep+0x1f9/0x4a0 kernel/time/hrtimer.c:2097 common_nsleep+0xa2/0xc0 kernel/time/posix-timers.c:1227 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1267 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1245 [inline] __x64_sys_clock_nanosleep+0x2f4/0x430 kernel/time/posix-timers.c:1245 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 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{2:2} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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:1505 kernel_wait+0x9c/0x150 kernel/exit.c:1695 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 *** 7 locks held by syz-executor.0/5873: #0: ffff888075d78098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffff888010c790b8 (&buf->lock){+.+.}-{3:3}, at: paste_selection+0x110/0x4c0 drivers/tty/vt/selection.c:390 #2: ffffffff8c39ca48 (vc_sel.lock){+.+.}-{3:3}, at: paste_selection+0x146/0x4c0 drivers/tty/vt/selection.c:393 #3: ffff888075d782e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_receive_buf_common+0x84/0x4780 drivers/tty/n_tty.c:1637 #4: ffffffff8b982da0 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x41/0x470 fs/fcntl.c:1033 #5: ffff888020ad9b40 (&new->fa_lock){.-.-}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1014 [inline] #5: ffff888020ad9b40 (&new->fa_lock){.-.-}-{2:2}, at: kill_fasync fs/fcntl.c:1035 [inline] #5: ffff888020ad9b40 (&new->fa_lock){.-.-}-{2:2}, at: kill_fasync+0x136/0x470 fs/fcntl.c:1028 #6: ffff888021f032b8 (&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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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_interrupt.part.0+0x34/0xcf0 sound/core/timer.c:857 snd_timer_interrupt sound/core/timer.c:1155 [inline] snd_timer_s_function+0x14b/0x200 sound/core/timer.c:1155 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 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 get_current arch/x86/include/asm/current.h:15 [inline] finish_task_switch.isra.0+0x323/0xb80 kernel/sched/core.c:4849 context_switch kernel/sched/core.c:4972 [inline] __schedule+0xaa2/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 freezable_schedule include/linux/freezer.h:172 [inline] do_nanosleep+0x24e/0x690 kernel/time/hrtimer.c:2044 hrtimer_nanosleep+0x1f9/0x4a0 kernel/time/hrtimer.c:2097 common_nsleep+0xa2/0xc0 kernel/time/posix-timers.c:1227 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1267 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1245 [inline] __x64_sys_clock_nanosleep+0x2f4/0x430 kernel/time/posix-timers.c:1245 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 USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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_resolution+0x55/0x100 sound/core/timer.c:489 snd_timer_user_params.isra.0+0x18e/0x8c0 sound/core/timer.c:1852 __snd_timer_user_ioctl.isra.0+0x1020/0x2490 sound/core/timer.c:2101 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.12+0x0/0x40 -> (&new->fa_lock){.-.-}-{2:2} { IN-HARDIRQ-R at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 get_current arch/x86/include/asm/current.h:15 [inline] __syscall_enter_from_user_work kernel/entry/common.c:87 [inline] syscall_enter_from_user_mode+0x2b/0x70 kernel/entry/common.c:108 do_syscall_64+0x16/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x44/0xae IN-SOFTIRQ-R at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 sock_wake_async+0xd2/0x160 net/socket.c:1368 sk_wake_async include/net/sock.h:2400 [inline] sk_wake_async include/net/sock.h:2396 [inline] sock_def_error_report+0x34b/0x4e0 net/core/sock.c:3125 sk_error_report+0x35/0x310 net/core/sock.c:339 tcp_write_err net/ipv4/tcp_timer.c:71 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:276 [inline] tcp_retransmit_timer+0x20c2/0x3320 net/ipv4/tcp_timer.c:512 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 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 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline] acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:553 acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:688 cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e8/0x590 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x265/0x340 arch/x86/kernel/smpboot.c:272 secondary_startup_64_no_verify+0xb0/0xbb INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 get_current arch/x86/include/asm/current.h:15 [inline] __syscall_enter_from_user_work kernel/entry/common.c:87 [inline] syscall_enter_from_user_mode+0x2b/0x70 kernel/entry/common.c:108 do_syscall_64+0x16/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x44/0xae IN-SOFTIRQ-R at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 sock_wake_async+0xd2/0x160 net/socket.c:1368 sk_wake_async include/net/sock.h:2400 [inline] sk_wake_async include/net/sock.h:2396 [inline] sock_def_error_report+0x34b/0x4e0 net/core/sock.c:3125 sk_error_report+0x35/0x310 net/core/sock.c:339 tcp_write_err net/ipv4/tcp_timer.c:71 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:276 [inline] tcp_retransmit_timer+0x20c2/0x3320 net/ipv4/tcp_timer.c:512 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 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 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline] acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:553 acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:688 cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e8/0x590 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x265/0x340 arch/x86/kernel/smpboot.c:272 secondary_startup_64_no_verify+0xb0/0xbb INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline] _raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316 f_modown+0x2a/0x390 fs/fcntl.c:91 fcntl_dirnotify+0x7c9/0xbc0 fs/notify/dnotify/dnotify.c:351 do_fcntl+0x269/0x1210 fs/fcntl.c:422 __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 INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 } ... 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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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:1505 kernel_wait+0x9c/0x150 kernel/exit.c:1695 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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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:1505 kernel_wait+0x9c/0x150 kernel/exit.c:1695 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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline] _raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316 copy_process+0x36c0/0x75a0 kernel/fork.c:2312 kernel_clone+0xe7/0xab0 kernel/fork.c:2583 kernel_thread+0xb5/0xf0 kernel/fork.c:2635 rest_init+0x23/0x3e0 init/main.c:690 start_kernel+0x47a/0x49b init/main.c:1133 secondary_startup_64_no_verify+0xb0/0xbb INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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:1505 kernel_wait+0x9c/0x150 kernel/exit.c:1695 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:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 __receive_buf drivers/tty/n_tty.c:1591 [inline] n_tty_receive_buf_common+0x12d7/0x4780 drivers/tty/n_tty.c:1674 tty_ldisc_receive_buf+0xa3/0x190 drivers/tty/tty_buffer.c:471 paste_selection+0x1de/0x4c0 drivers/tty/vt/selection.c:408 tioclinux+0x126/0x560 drivers/tty/vt/vt.c:3204 vt_ioctl+0x229a/0x2b10 drivers/tty/vt/vt_ioctl.c:762 tty_ioctl+0xbbd/0x1670 drivers/tty/tty_io.c:2805 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 stack backtrace: CPU: 1 PID: 5873 Comm: syz-executor.0 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+0xcd/0x134 lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2565 [inline] check_irq_usage.cold+0x4c1/0x6b0 kernel/locking/lockdep.c:2804 check_prev_add kernel/locking/lockdep.c:3055 [inline] check_prevs_add kernel/locking/lockdep.c:3174 [inline] validate_chain kernel/locking/lockdep.c:3789 [inline] __lock_acquire+0x2a1f/0x54a0 kernel/locking/lockdep.c:5015 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __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 __receive_buf drivers/tty/n_tty.c:1591 [inline] n_tty_receive_buf_common+0x12d7/0x4780 drivers/tty/n_tty.c:1674 tty_ldisc_receive_buf+0xa3/0x190 drivers/tty/tty_buffer.c:471 paste_selection+0x1de/0x4c0 drivers/tty/vt/selection.c:408 tioclinux+0x126/0x560 drivers/tty/vt/vt.c:3204 vt_ioctl+0x229a/0x2b10 drivers/tty/vt/vt_ioctl.c:762 tty_ioctl+0xbbd/0x1670 drivers/tty/tty_io.c:2805 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 RIP: 0033:0x7f4d54db1ae9 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:00007f4d52327188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4d54ec4f60 RCX: 00007f4d54db1ae9 RDX: 0000000020000100 RSI: 000000000000541c RDI: 0000000000000004 RBP: 00007f4d54e0bf25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff93511a3f R14: 00007f4d52327300 R15: 0000000000022000