======================================================== WARNING: possible irq lock inversion dependency detected 6.15.0-syzkaller-08297-ge0797d3b91de #0 Not tainted -------------------------------------------------------- ksoftirqd/1/23 just changed the state of lock: ffff888146b4c230 (&dev->event_lock#2){..-.}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] ffff888146b4c230 (&dev->event_lock#2){..-.}-{3:3}, at: input_inject_event+0xab/0x320 drivers/input/input.c:418 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#2 --> &new->fa_lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock#2); lock(&new->fa_lock); lock(&dev->event_lock#2); *** DEADLOCK *** 1 lock held by ksoftirqd/1/23: #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: led_trigger_event+0x4b/0x210 drivers/leds/led-triggers.c:405 the shortest dependencies between 2nd lock and 1st lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1668 do_wait+0x1f8/0x520 kernel/exit.c:1712 kernel_wait+0xab/0x170 kernel/exit.c:1888 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 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+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1668 do_wait+0x1f8/0x520 kernel/exit.c:1712 kernel_wait+0xab/0x170 kernel/exit.c:1888 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 copy_process+0x224f/0x3c00 kernel/fork.c:2575 kernel_clone+0x21e/0x870 kernel/fork.c:2859 user_mode_thread+0xdd/0x140 kernel/fork.c:2937 rest_init+0x23/0x300 init/main.c:708 start_kernel+0x478/0x500 init/main.c:1099 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1668 do_wait+0x1f8/0x520 kernel/exit.c:1712 kernel_wait+0xab/0x170 kernel/exit.c:1888 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 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+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigio+0x101/0x370 fs/fcntl.c:921 dnotify_handle_event+0x169/0x440 fs/notify/dnotify/dnotify.c:113 fsnotify_handle_event fs/notify/fsnotify.c:376 [inline] send_to_group fs/notify/fsnotify.c:424 [inline] fsnotify+0x1814/0x1a80 fs/notify/fsnotify.c:641 fsnotify_name include/linux/fsnotify.h:55 [inline] fsnotify_dirent include/linux/fsnotify.h:61 [inline] fsnotify_mkdir include/linux/fsnotify.h:429 [inline] vfs_mkdir+0x477/0x510 fs/namei.c:4374 do_mkdirat+0x247/0x590 fs/namei.c:4399 __do_sys_mkdir fs/namei.c:4421 [inline] __se_sys_mkdir fs/namei.c:4419 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 __f_setown+0x67/0x370 fs/fcntl.c:136 fcntl_dirnotify+0x3d6/0x690 fs/notify/dnotify/dnotify.c:369 do_fcntl+0x6d0/0x1910 fs/fcntl.c:539 __do_sys_fcntl fs/fcntl.c:591 [inline] __se_sys_fcntl+0xc8/0x150 fs/fcntl.c:576 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 send_sigio+0x38/0x370 fs/fcntl.c:907 dnotify_handle_event+0x169/0x440 fs/notify/dnotify/dnotify.c:113 fsnotify_handle_event fs/notify/fsnotify.c:376 [inline] send_to_group fs/notify/fsnotify.c:424 [inline] fsnotify+0x1814/0x1a80 fs/notify/fsnotify.c:641 fsnotify_name include/linux/fsnotify.h:55 [inline] fsnotify_dirent include/linux/fsnotify.h:61 [inline] fsnotify_mkdir include/linux/fsnotify.h:429 [inline] vfs_mkdir+0x477/0x510 fs/namei.c:4374 do_mkdirat+0x247/0x590 fs/namei.c:4399 __do_sys_mkdir fs/namei.c:4421 [inline] __se_sys_mkdir fs/namei.c:4419 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] file_f_owner_allocate.__key+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 send_sigio+0x38/0x370 fs/fcntl.c:907 kill_fasync_rcu fs/fcntl.c:1133 [inline] kill_fasync+0x24d/0x4d0 fs/fcntl.c:1148 lease_break_callback+0x26/0x30 fs/locks.c:558 __break_lease+0x6a5/0x1620 fs/locks.c:1592 break_lease include/linux/filelock.h:441 [inline] do_dentry_open+0xd62/0x1970 fs/open.c:955 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3887 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_open fs/open.c:1460 [inline] __se_sys_open fs/open.c:1456 [inline] __x64_sys_open+0x11e/0x150 fs/open.c:1456 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&new->fa_lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 fasync_remove_entry+0xf1/0x1c0 fs/fcntl.c:1001 __fput+0x8a2/0xa70 fs/file_table.c:462 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1124 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1148 fuse_abort_conn+0xcf1/0x1010 fs/fuse/dev.c:2436 cuse_process_init_reply+0x89e/0xe20 fs/fuse/cuse.c:425 fuse_request_end+0x7b3/0xa60 fs/fuse/dev.c:486 fuse_dev_do_write+0x1c21/0x5010 fs/fuse/dev.c:2194 fuse_dev_write+0x143/0x1d0 fs/fuse/dev.c:2216 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1124 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1148 mousedev_notify_readers+0x6f1/0xc00 drivers/input/mousedev.c:309 mousedev_event+0x602/0x1320 drivers/input/mousedev.c:394 input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2575 input_pass_values+0x288/0x890 drivers/input/input.c:127 input_event_dispose+0x330/0x6b0 drivers/input/input.c:341 input_inject_event+0x1fe/0x320 drivers/input/input.c:423 evdev_write+0x2fc/0x480 drivers/input/evdev.c:528 vfs_write+0x27e/0xa90 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&dev->event_lock#2){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 led_trigger_event+0x138/0x210 drivers/leds/led-triggers.c:407 kbd_propagate_led_state drivers/tty/vt/keyboard.c:1080 [inline] kbd_bh+0x1c6/0x2e0 drivers/tty/vt/keyboard.c:1269 tasklet_action_common+0x36c/0x580 kernel/softirq.c:829 handle_softirqs+0x286/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:164 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 kbd_led_trigger_activate+0xbc/0x100 drivers/tty/vt/keyboard.c:1036 led_trigger_set+0x52d/0x950 drivers/leds/led-triggers.c:212 led_match_default_trigger drivers/leds/led-triggers.c:269 [inline] led_trigger_set_default+0x215/0x250 drivers/leds/led-triggers.c:287 led_classdev_register_ext+0x73d/0x930 drivers/leds/led-class.c:566 led_classdev_register include/linux/leds.h:274 [inline] input_leds_connect+0x517/0x790 drivers/input/input-leds.c:145 input_attach_handler drivers/input/input.c:993 [inline] input_register_device+0xcee/0x10b0 drivers/input/input.c:2412 atkbd_connect+0x70e/0x9c0 drivers/input/keyboard/atkbd.c:1340 serio_connect_driver drivers/input/serio/serio.c:43 [inline] serio_driver_probe+0x82/0xa0 drivers/input/serio/serio.c:747 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9a0 drivers/base/dd.c:657 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829 __driver_attach+0x452/0x700 drivers/base/dd.c:1215 bus_for_each_dev+0x233/0x2b0 drivers/base/bus.c:370 serio_attach_driver drivers/input/serio/serio.c:776 [inline] serio_handle_event+0x1a2/0x860 drivers/input/serio/serio.c:213 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] input_allocate_device.__key.5+0x0/0x20 ... acquired at: mark_lock+0x11b/0x190 kernel/locking/lockdep.c:4756 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0x680/0xd20 kernel/locking/lockdep.c:5194 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 led_trigger_event+0x138/0x210 drivers/leds/led-triggers.c:407 kbd_propagate_led_state drivers/tty/vt/keyboard.c:1080 [inline] kbd_bh+0x1c6/0x2e0 drivers/tty/vt/keyboard.c:1269 tasklet_action_common+0x36c/0x580 kernel/softirq.c:829 handle_softirqs+0x286/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:164 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 stack backtrace: CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_irq_inversion_bug+0x1d2/0x1e0 kernel/locking/lockdep.c:4128 mark_lock_irq+0x35f/0x390 kernel/locking/lockdep.c:-1 mark_lock+0x11b/0x190 kernel/locking/lockdep.c:4756 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0x680/0xd20 kernel/locking/lockdep.c:5194 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 led_trigger_event+0x138/0x210 drivers/leds/led-triggers.c:407 kbd_propagate_led_state drivers/tty/vt/keyboard.c:1080 [inline] kbd_bh+0x1c6/0x2e0 drivers/tty/vt/keyboard.c:1269 tasklet_action_common+0x36c/0x580 kernel/softirq.c:829 handle_softirqs+0x286/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:164 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245