======================================================== WARNING: possible irq lock inversion dependency detected 6.19.0-rc1-next-20251215 #1 Not tainted -------------------------------------------------------- ksoftirqd/0/14 just changed the state of lock: ffff88800a65f230 (&dev->event_lock){..-.}-{3:3}, at: input_inject_event+0x9f/0x3b0 but this lock took another, SOFTIRQ-READ-unsafe lock in the past: (tasklist_lock){.+.+}-{3:3} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Chain exists of: &dev->event_lock --> &client->buffer_lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock); lock(&client->buffer_lock); lock(&dev->event_lock); *** DEADLOCK *** 1 lock held by ksoftirqd/0/14: #0: ffffffff85e21c20 (rcu_read_lock){....}-{1:3}, at: led_trigger_event+0x61/0x270 the shortest dependencies between 2nd lock and 1st lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 SOFTIRQ-ON-R at: lock_acquire+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_write_lock_irq+0x33/0x50 copy_process+0x4e71/0x7230 kernel_clone+0xea/0x7c0 user_mode_thread+0xc8/0x110 rest_init+0x24/0x290 start_kernel+0x3fa/0x510 x86_64_start_reservations+0x18/0x30 x86_64_start_kernel+0x109/0x120 common_startup_64+0x13e/0x148 INITIAL READ USE at: lock_acquire+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: _raw_read_lock+0x5c/0x70 send_sigio+0xbb/0x370 kill_fasync+0x218/0x520 lease_break_callback+0x23/0x30 __break_lease+0x6c4/0x1760 vfs_truncate+0x30d/0x480 do_sys_truncate.part.0+0xfa/0x140 __x64_sys_truncate+0x6d/0xa0 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_write_lock_irq+0x33/0x50 __f_setown+0x60/0x3c0 generic_setlease+0xfb4/0x16e0 kernel_setlease+0x10c/0x130 vfs_setlease+0x1f1/0x290 do_fcntl_add_lease+0x3b0/0x540 fcntl_setlease+0xfa/0x180 do_fcntl+0x4e3/0x1500 __x64_sys_fcntl+0x155/0x1f0 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x75/0x90 send_sigio+0x31/0x370 kill_fasync+0x218/0x520 lease_break_callback+0x23/0x30 __break_lease+0x6c4/0x1760 vfs_truncate+0x30d/0x480 do_sys_truncate.part.0+0xfa/0x140 __x64_sys_truncate+0x6d/0xa0 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.1+0x0/0x40 ... acquired at: _raw_read_lock_irqsave+0x75/0x90 send_sigio+0x31/0x370 kill_fasync+0x218/0x520 lease_break_callback+0x23/0x30 __break_lease+0x6c4/0x1760 vfs_truncate+0x30d/0x480 do_sys_truncate.part.0+0xfa/0x140 __x64_sys_truncate+0x6d/0xa0 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&new->fa_lock){.-.-}-{3:3} { IN-HARDIRQ-R at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x46/0x90 kill_fasync+0x137/0x520 perf_pending_irq+0x210/0x360 irq_work_single+0x128/0x260 irq_work_run_list+0x91/0xc0 irq_work_run+0x1d/0x40 __sysvec_irq_work+0x6d/0x310 sysvec_irq_work+0xa1/0xc0 asm_sysvec_irq_work+0x1a/0x20 _raw_spin_unlock_irqrestore+0x34/0x50 try_to_wake_up+0x99f/0x1660 wake_up_q+0xa1/0x130 futex_wake+0x47e/0x540 do_futex+0x26d/0x370 __x64_sys_futex+0x1c9/0x4d0 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f IN-SOFTIRQ-R at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x46/0x90 kill_fasync+0x137/0x520 perf_pending_irq+0x210/0x360 irq_work_single+0x128/0x260 irq_work_run_list+0x91/0xc0 irq_work_run+0x1d/0x40 __sysvec_irq_work+0x6d/0x310 sysvec_irq_work+0x5f/0xc0 asm_sysvec_irq_work+0x1a/0x20 rcu_core+0x6ae/0x1fb0 handle_softirqs+0x1b1/0x7d0 __irq_exit_rcu+0xc4/0x100 irq_exit_rcu+0x9/0x20 sysvec_apic_timer_interrupt+0x70/0x80 asm_sysvec_apic_timer_interrupt+0x1a/0x20 _raw_spin_unlock_irqrestore+0x34/0x50 mm_cid_fixup_task_to_cpu+0x188/0x450 sched_mm_cid_fork+0x660/0xcf0 copy_process+0x2607/0x7230 kernel_clone+0xea/0x7c0 __do_sys_clone3+0x1f5/0x280 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_write_lock_irq+0x33/0x50 fasync_remove_entry+0xb2/0x1e0 fasync_helper+0xa6/0xc0 lease_modify+0x2ab/0x620 locks_remove_file+0x294/0x5a0 __fput+0x351/0xb50 fput_close_sync+0x10f/0x230 __x64_sys_close+0x8f/0x120 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x75/0x90 kill_fasync+0x137/0x520 anon_pipe_read+0x9a9/0xd10 do_iter_readv_writev+0x691/0x910 vfs_readv+0x42b/0x7f0 do_readv+0x283/0x330 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.0+0x0/0x40 ... acquired at: _raw_read_lock_irqsave+0x75/0x90 kill_fasync+0x137/0x520 evdev_pass_values.part.0+0x665/0x940 evdev_events+0x3b5/0x430 input_pass_values+0x708/0x860 input_handle_event+0xdcf/0x13d0 input_inject_event+0x1e5/0x3b0 evdev_write+0x2e1/0x420 vfs_write+0x2b7/0x1150 ksys_write+0x1ef/0x240 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&client->buffer_lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_spin_lock+0x2b/0x40 evdev_handle_get_val+0x70/0x5c0 evdev_do_ioctl+0xf6d/0x1990 evdev_ioctl+0x14a/0x1b0 __x64_sys_ioctl+0x18f/0x210 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.93+0x0/0x40 ... acquired at: _raw_spin_lock+0x2b/0x40 evdev_handle_get_val+0x70/0x5c0 evdev_do_ioctl+0xf6d/0x1990 evdev_ioctl+0x14a/0x1b0 __x64_sys_ioctl+0x18f/0x210 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&dev->event_lock){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 led_trigger_event+0xda/0x270 kbd_bh+0x23a/0x310 tasklet_action_common+0x270/0x730 handle_softirqs+0x1b1/0x7d0 run_ksoftirqd+0x2e/0x60 smpboot_thread_fn+0x41d/0x9d0 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 kbd_led_trigger_activate+0xcd/0x110 led_trigger_set+0x4cc/0xaa0 led_trigger_set_default+0x1e7/0x2e0 led_classdev_register_ext+0x615/0x950 input_leds_connect+0x49b/0x870 input_attach_handler+0x17a/0x260 input_register_device+0x9ff/0x1050 atkbd_connect+0x5e6/0xa10 serio_driver_probe+0x84/0xe0 really_probe+0x240/0x820 __driver_probe_device+0x2c4/0x380 driver_probe_device+0x4e/0x2a0 __driver_attach+0x1b0/0x590 bus_for_each_dev+0x12b/0x1c0 serio_handle_event+0x23b/0xaa0 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 } ... key at: [] __key.4+0x0/0x40 ... acquired at: __lock_acquire+0x975/0x2250 lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 led_trigger_event+0xda/0x270 kbd_bh+0x23a/0x310 tasklet_action_common+0x270/0x730 handle_softirqs+0x1b1/0x7d0 run_ksoftirqd+0x2e/0x60 smpboot_thread_fn+0x41d/0x9d0 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 stack backtrace: CPU: 0 UID: 0 PID: 14 Comm: ksoftirqd/0 Not tainted 6.19.0-rc1-next-20251215 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0xca/0x120 print_irq_inversion_bug.part.0+0x20a/0x260 mark_lock+0x850/0xf70 __lock_acquire+0x975/0x2250 lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 led_trigger_event+0xda/0x270 kbd_bh+0x23a/0x310 tasklet_action_common+0x270/0x730 handle_softirqs+0x1b1/0x7d0 run_ksoftirqd+0x2e/0x60 smpboot_thread_fn+0x41d/0x9d0 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 Process accounting paused