===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 6.16.0-syzkaller-11699-g7e161a991ea7 #0 Not tainted ----------------------------------------------------- syz.4.2365/14785 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8e20c098 (tasklist_lock){.+.+}-{3:3}, at: send_sigurg+0xed/0xc80 fs/fcntl.c:967 and this task is already holding: ffff888078d5ea20 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x5f/0xc80 fs/fcntl.c:951 which would create a new lock dependency: (&f_owner->lock){....}-{3:3} -> (tasklist_lock){.+.+}-{3:3} but this new dependency connects a SOFTIRQ-irq-safe lock: (&dev->event_lock#2){..-.}-{3:3} ... which became SOFTIRQ-irq-safe at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_event drivers/input/input.c:394 [inline] input_event+0x74/0xd0 drivers/input/input.c:390 input_sync include/linux/input.h:464 [inline] hidinput_report_event+0xb2/0x100 drivers/hid/hid-input.c:1733 hid_report_raw_event+0x268/0x1290 drivers/hid/hid-core.c:2072 __hid_input_report.constprop.0+0x33f/0x450 drivers/hid/hid-core.c:2135 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x38a/0x6e0 drivers/usb/core/hcd.c:1663 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1747 dummy_timer+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 queue_work_on+0x86/0x1f0 kernel/workqueue.c:2383 driver_deferred_probe_trigger drivers/base/dd.c:178 [inline] driver_bound+0x145/0x230 drivers/base/dd.c:419 really_probe+0x62b/0xa90 drivers/base/dd.c:709 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1aa0 drivers/base/core.c:3689 hid_add_device+0x373/0xa60 drivers/hid/hid-core.c:2923 usbhid_probe+0xd38/0x13f0 drivers/hid/usbhid/hid-core.c:1435 usb_probe_interface+0x303/0xa40 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1aa0 drivers/base/core.c:3689 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1aa0 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a60 drivers/usb/core/hub.c:2694 hub_port_connect drivers/usb/core/hub.c:5566 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{3:3} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1662 do_wait+0x21e/0x5a0 kernel/exit.c:1706 kernel_wait+0x9f/0x160 kernel/exit.c:1882 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: &dev->event_lock#2 --> &f_owner->lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock#2); lock(&f_owner->lock); lock(&dev->event_lock#2); *** DEADLOCK *** 2 locks held by syz.4.2365/14785: #0: ffff88805ab786c0 (&u->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #0: ffff88805ab786c0 (&u->lock){+.+.}-{3:3}, at: queue_oob net/unix/af_unix.c:2359 [inline] #0: ffff88805ab786c0 (&u->lock){+.+.}-{3:3}, at: unix_stream_sendmsg+0xd35/0x1340 net/unix/af_unix.c:2516 #1: ffff888078d5ea20 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x5f/0xc80 fs/fcntl.c:951 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&dev->event_lock#2){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_event drivers/input/input.c:394 [inline] input_event+0x74/0xd0 drivers/input/input.c:390 input_sync include/linux/input.h:464 [inline] hidinput_report_event+0xb2/0x100 drivers/hid/hid-input.c:1733 hid_report_raw_event+0x268/0x1290 drivers/hid/hid-core.c:2072 __hid_input_report.constprop.0+0x33f/0x450 drivers/hid/hid-core.c:2135 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x38a/0x6e0 drivers/usb/core/hcd.c:1663 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1747 dummy_timer+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 queue_work_on+0x86/0x1f0 kernel/workqueue.c:2383 driver_deferred_probe_trigger drivers/base/dd.c:178 [inline] driver_bound+0x145/0x230 drivers/base/dd.c:419 really_probe+0x62b/0xa90 drivers/base/dd.c:709 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1aa0 drivers/base/core.c:3689 hid_add_device+0x373/0xa60 drivers/hid/hid-core.c:2923 usbhid_probe+0xd38/0x13f0 drivers/hid/usbhid/hid-core.c:1435 usb_probe_interface+0x303/0xa40 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1aa0 drivers/base/core.c:3689 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1aa0 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a60 drivers/usb/core/hub.c:2694 hub_port_connect drivers/usb/core/hub.c:5566 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0x9f/0x3b0 drivers/input/input.c:418 __led_set_brightness drivers/leds/led-core.c:52 [inline] led_set_brightness_nopm drivers/leds/led-core.c:335 [inline] led_set_brightness_nosleep drivers/leds/led-core.c:369 [inline] led_set_brightness+0x217/0x290 drivers/leds/led-core.c:328 kbd_led_trigger_activate+0xcb/0x110 drivers/tty/vt/keyboard.c:1029 led_trigger_set+0x59a/0xc50 drivers/leds/led-triggers.c:220 led_match_default_trigger drivers/leds/led-triggers.c:277 [inline] led_match_default_trigger drivers/leds/led-triggers.c:271 [inline] led_trigger_set_default drivers/leds/led-triggers.c:300 [inline] led_trigger_set_default+0x1e0/0x2e0 drivers/leds/led-triggers.c:284 led_classdev_register_ext+0x7b8/0xa10 drivers/leds/led-class.c:565 led_classdev_register include/linux/leds.h:274 [inline] input_leds_connect+0x552/0x8e0 drivers/input/input-leds.c:145 input_attach_handler.isra.0+0x184/0x260 drivers/input/input.c:993 input_register_device+0xab9/0x1180 drivers/input/input.c:2412 atkbd_connect+0x5f8/0xa40 drivers/input/keyboard/atkbd.c:1340 serio_connect_driver drivers/input/serio/serio.c:43 [inline] serio_driver_probe+0x7f/0xd0 drivers/input/serio/serio.c:747 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __driver_attach+0x283/0x580 drivers/base/dd.c:1217 bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:370 serio_attach_driver drivers/input/serio/serio.c:776 [inline] serio_handle_event+0x335/0xc30 drivers/input/serio/serio.c:213 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] __key.7+0x0/0x40 -> (&new->fa_lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 fasync_insert_entry+0x1ca/0x2a0 fs/fcntl.c:1048 fasync_add_entry fs/fcntl.c:1087 [inline] fasync_helper+0x60/0xd0 fs/fcntl.c:1105 sock_fasync+0x92/0x140 net/socket.c:1464 ioctl_fioasync fs/ioctl.c:379 [inline] do_vfs_ioctl+0xa08/0x14f0 fs/ioctl.c:512 __do_sys_ioctl fs/ioctl.c:596 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __x64_sys_ioctl+0x114/0x210 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1124 [inline] kill_fasync fs/fcntl.c:1148 [inline] kill_fasync+0x138/0x510 fs/fcntl.c:1141 pipe_release+0x191/0x320 fs/pipe.c:737 __fput+0x3ff/0xb70 fs/file_table.c:468 task_work_run+0x14d/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.0+0x0/0x40 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1124 [inline] kill_fasync fs/fcntl.c:1148 [inline] kill_fasync+0x138/0x510 fs/fcntl.c:1141 mousedev_notify_readers+0x6d8/0xa30 drivers/input/mousedev.c:309 mousedev_event+0x84e/0x1490 drivers/input/mousedev.c:394 input_handle_events_default+0x119/0x1b0 drivers/input/input.c:2575 input_pass_values+0x74e/0x880 drivers/input/input.c:127 input_event_dispose drivers/input/input.c:341 [inline] input_handle_event+0xf00/0x14d0 drivers/input/input.c:369 input_inject_event+0x1e8/0x3b0 drivers/input/input.c:423 evdev_write+0x457/0x750 drivers/input/evdev.c:528 vfs_write+0x29d/0x1150 fs/read_write.c:684 ksys_write+0x1f8/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 __f_setown+0x61/0x3c0 fs/fcntl.c:136 f_setown+0x122/0x290 fs/fcntl.c:183 do_fcntl+0xfa6/0x15a0 fs/fcntl.c:515 __do_sys_fcntl fs/fcntl.c:591 [inline] __se_sys_fcntl fs/fcntl.c:576 [inline] __x64_sys_fcntl+0x163/0x200 fs/fcntl.c:576 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 send_sigio+0x31/0x3e0 fs/fcntl.c:907 kill_fasync_rcu fs/fcntl.c:1133 [inline] kill_fasync fs/fcntl.c:1148 [inline] kill_fasync+0x214/0x510 fs/fcntl.c:1141 tty_wakeup+0xe8/0x120 drivers/tty/tty_io.c:515 pty_unthrottle+0x37/0x60 drivers/tty/pty.c:95 tty_unthrottle+0xac/0x110 drivers/tty/tty_ioctl.c:106 __tty_perform_flush+0x1bc/0x210 drivers/tty/tty_ioctl.c:903 n_tty_ioctl_helper+0x148/0x2b0 drivers/tty/tty_ioctl.c:979 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.1+0x0/0x40 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 send_sigio+0x31/0x3e0 fs/fcntl.c:907 kill_fasync_rcu fs/fcntl.c:1133 [inline] kill_fasync fs/fcntl.c:1148 [inline] kill_fasync+0x214/0x510 fs/fcntl.c:1141 tty_wakeup+0xe8/0x120 drivers/tty/tty_io.c:515 pty_unthrottle+0x37/0x60 drivers/tty/pty.c:95 tty_unthrottle+0xac/0x110 drivers/tty/tty_ioctl.c:106 __tty_perform_flush+0x1bc/0x210 drivers/tty/tty_ioctl.c:903 n_tty_ioctl_helper+0x148/0x2b0 drivers/tty/tty_ioctl.c:979 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1662 do_wait+0x21e/0x5a0 kernel/exit.c:1706 kernel_wait+0x9f/0x160 kernel/exit.c:1882 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 SOFTIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1662 do_wait+0x21e/0x5a0 kernel/exit.c:1706 kernel_wait+0x9f/0x160 kernel/exit.c:1882 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 copy_process+0x4caf/0x7690 kernel/fork.c:2318 kernel_clone+0xfc/0x930 kernel/fork.c:2602 user_mode_thread+0xc7/0x110 kernel/fork.c:2680 rest_init+0x23/0x2b0 init/main.c:709 start_kernel+0x3ee/0x4d0 init/main.c:1097 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1662 do_wait+0x21e/0x5a0 kernel/exit.c:1706 kernel_wait+0x9f/0x160 kernel/exit.c:1882 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 send_sigurg+0xed/0xc80 fs/fcntl.c:967 sk_send_sigurg+0x76/0x360 net/core/sock.c:3622 queue_oob net/unix/af_unix.c:2380 [inline] unix_stream_sendmsg+0xfa5/0x1340 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmmsg+0x200/0x420 net/socket.c:2757 __do_sys_sendmmsg net/socket.c:2784 [inline] __se_sys_sendmmsg net/socket.c:2781 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2781 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 0 UID: 0 PID: 14785 Comm: syz.4.2365 Not tainted 6.16.0-syzkaller-11699-g7e161a991ea7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2616 [inline] check_irq_usage+0x7dc/0x920 kernel/locking/lockdep.c:2857 check_prev_add kernel/locking/lockdep.c:3169 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x12bc/0x1ce0 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 send_sigurg+0xed/0xc80 fs/fcntl.c:967 sk_send_sigurg+0x76/0x360 net/core/sock.c:3622 queue_oob net/unix/af_unix.c:2380 [inline] unix_stream_sendmsg+0xfa5/0x1340 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmmsg+0x200/0x420 net/socket.c:2757 __do_sys_sendmmsg net/socket.c:2784 [inline] __se_sys_sendmmsg net/socket.c:2781 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2781 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f844658eb69 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f84443f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f84467b5fa0 RCX: 00007f844658eb69 RDX: 0000000000000001 RSI: 0000200000006c40 RDI: 0000000000000004 RBP: 00007f8446611df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000040015 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f84467b5fa0 R15: 00007ffd5c4f1768