usb 7-1: unknown answer from device input input38: Pen battery low ======================================================== WARNING: possible irq lock inversion dependency detected syzkaller #0 Tainted: G L -------------------------------------------------------- syz-executor/13215 just changed the state of lock: ffff88802d0e7230 (&dev->event_lock#2){..-.}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] ffff88802d0e7230 (&dev->event_lock#2){..-.}-{3:3}, at: input_event drivers/input/input.c:395 [inline] ffff88802d0e7230 (&dev->event_lock#2){..-.}-{3:3}, at: input_event+0x74/0xd0 drivers/input/input.c:391 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 --> &client->buffer_lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock#2); lock(&client->buffer_lock); lock(&dev->event_lock#2); *** DEADLOCK *** 3 locks held by syz-executor/13215: #0: ffff888028f76420 (sb_writers#3){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:4529 [inline] #0: ffff888028f76420 (sb_writers#3){.+.+}-{0:0}, at: path_openat+0x183a/0x3140 fs/namei.c:4784 #1: ffff888043549bd0 (&sb->s_type->i_mutex_key#12){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #1: ffff888043549bd0 (&sb->s_type->i_mutex_key#12){++++}-{4:4}, at: open_last_lookups fs/namei.c:4539 [inline] #1: ffff888043549bd0 (&sb->s_type->i_mutex_key#12){++++}-{4:4}, at: path_openat+0x1248/0x3140 fs/namei.c:4784 #2: ffffffff8e3c9460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8e3c9460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #2: ffffffff8e3c9460 (rcu_read_lock){....}-{1:3}, at: get_pid_task+0x2a/0x250 kernel/pid.c:469 the shortest dependencies between 2nd lock and 1st lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:1674 do_wait+0x21d/0x570 kernel/exit.c:1718 kernel_wait+0x9f/0x160 kernel/exit.c:1894 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 SOFTIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:1674 do_wait+0x21d/0x570 kernel/exit.c:1718 kernel_wait+0x9f/0x160 kernel/exit.c:1894 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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+0x4185/0x74e0 kernel/fork.c:2324 kernel_clone+0xfc/0x910 kernel/fork.c:2608 user_mode_thread+0xc8/0x110 kernel/fork.c:2684 rest_init+0x23/0x2b0 init/main.c:722 start_kernel+0x3f6/0x4d0 init/main.c:1111 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:1674 do_wait+0x21d/0x570 kernel/exit.c:1718 kernel_wait+0x9f/0x160 kernel/exit.c:1894 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: __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:978 sk_send_sigurg+0x76/0x360 net/core/sock.c:3669 queue_oob net/unix/af_unix.c:2357 [inline] unix_stream_sendmsg+0xfa3/0x1320 net/unix/af_unix.c:2491 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 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+0x179/0x330 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 sock_ioctl+0x467/0x6b0 net/socket.c:1316 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 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+0x179/0x330 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_sigurg+0x5f/0xc80 fs/fcntl.c:962 sk_send_sigurg+0x76/0x360 net/core/sock.c:3669 queue_oob net/unix/af_unix.c:2357 [inline] unix_stream_sendmsg+0xfa3/0x1320 net/unix/af_unix.c:2491 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 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:918 kill_fasync_rcu fs/fcntl.c:1144 [inline] kill_fasync fs/fcntl.c:1159 [inline] kill_fasync+0x214/0x510 fs/fcntl.c:1152 sock_wake_async+0x132/0x160 net/socket.c:1509 sk_wake_async_rcu include/net/sock.h:2570 [inline] sk_wake_async_rcu include/net/sock.h:2567 [inline] sock_def_readable+0x4f7/0x5d0 net/core/sock.c:3613 queue_oob net/unix/af_unix.c:2359 [inline] unix_stream_sendmsg+0xfdb/0x1320 net/unix/af_unix.c:2491 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&new->fa_lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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_remove_entry+0xb2/0x1e0 fs/fcntl.c:1012 fasync_helper+0xaf/0xd0 fs/fcntl.c:1115 pipe_fasync+0xc7/0x200 fs/pipe.c:758 __fput+0x96b/0xb70 fs/file_table.c:465 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xfb/0x540 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:1135 [inline] kill_fasync fs/fcntl.c:1159 [inline] kill_fasync+0x138/0x510 fs/fcntl.c:1152 wakeup_pipe_writers fs/splice.c:420 [inline] splice_from_pipe_end fs/splice.c:581 [inline] __splice_from_pipe+0x663/0x800 fs/splice.c:609 vmsplice_to_user fs/splice.c:1521 [inline] __do_sys_vmsplice+0x707/0xef0 fs/splice.c:1612 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 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:1135 [inline] kill_fasync fs/fcntl.c:1159 [inline] kill_fasync+0x138/0x510 fs/fcntl.c:1152 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x619/0x9b0 drivers/input/evdev.c:278 evdev_events+0x1bb/0x390 drivers/input/evdev.c:306 input_pass_values+0x74e/0x880 drivers/input/input.c:128 input_event_dispose drivers/input/input.c:342 [inline] input_handle_event+0xf00/0x14d0 drivers/input/input.c:370 input_inject_event+0x1e8/0x3b0 drivers/input/input.c:424 evdev_write+0x457/0x750 drivers/input/evdev.c:528 vfs_write+0x2a0/0x11d0 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/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&client->buffer_lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] evdev_pass_values+0x10e/0x9b0 drivers/input/evdev.c:261 evdev_events+0x1bb/0x390 drivers/input/evdev.c:306 input_pass_values+0x74e/0x880 drivers/input/input.c:128 input_event_dispose drivers/input/input.c:342 [inline] input_handle_event+0xf00/0x14d0 drivers/input/input.c:370 input_inject_event+0x1e8/0x3b0 drivers/input/input.c:424 evdev_write+0x457/0x750 drivers/input/evdev.c:528 vfs_write+0x2a0/0x11d0 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/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.88+0x0/0x40 ... acquired at: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] evdev_pass_values+0x10e/0x9b0 drivers/input/evdev.c:261 evdev_events+0x1bb/0x390 drivers/input/evdev.c:306 input_pass_values+0x74e/0x880 drivers/input/input.c:128 input_event_dispose drivers/input/input.c:342 [inline] input_handle_event+0xf00/0x14d0 drivers/input/input.c:370 input_inject_event+0x1e8/0x3b0 drivers/input/input.c:424 evdev_write+0x457/0x750 drivers/input/evdev.c:528 vfs_write+0x2a0/0x11d0 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/0xf80 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 kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:395 [inline] input_event+0x74/0xd0 drivers/input/input.c:391 input_report_key include/linux/input.h:439 [inline] pegasus_parse_packet drivers/input/tablet/pegasus_notetaker.c:163 [inline] pegasus_irq+0x42c/0x630 drivers/input/tablet/pegasus_notetaker.c:186 __usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745 dummy_timer+0x1809/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x219/0x8b0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 __refcount_add include/linux/refcount.h:290 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] get_task_struct include/linux/sched/task.h:116 [inline] get_pid_task+0xbb/0x250 kernel/pid.c:472 get_proc_task fs/proc/internal.h:149 [inline] proc_pident_lookup+0x49/0x270 fs/proc/base.c:2715 lookup_open.isra.0+0x4e2/0x1780 fs/namei.c:4413 open_last_lookups fs/namei.c:4540 [inline] path_openat+0x12bb/0x3140 fs/namei.c:4784 do_filp_open+0x20b/0x470 fs/namei.c:4814 do_sys_openat2+0x11f/0x280 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:419 __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:578 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+0x176/0x250 drivers/input/input.c:994 input_register_device+0xab9/0x1180 drivers/input/input.c:2378 atkbd_connect+0x5f8/0xa40 drivers/input/keyboard/atkbd.c:1340 serio_connect_driver drivers/input/serio/serio.c:44 [inline] serio_driver_probe+0x7f/0xd0 drivers/input/serio/serio.c:748 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:1225 bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:370 serio_attach_driver drivers/input/serio/serio.c:777 [inline] serio_handle_event+0x281/0xb30 drivers/input/serio/serio.c:214 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 } ... key at: [] __key.7+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4642 [inline] __lock_acquire+0xc3d/0x22f0 kernel/locking/lockdep.c:5191 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:395 [inline] input_event+0x74/0xd0 drivers/input/input.c:391 input_report_key include/linux/input.h:439 [inline] pegasus_parse_packet drivers/input/tablet/pegasus_notetaker.c:163 [inline] pegasus_irq+0x42c/0x630 drivers/input/tablet/pegasus_notetaker.c:186 __usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745 dummy_timer+0x1809/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x219/0x8b0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 __refcount_add include/linux/refcount.h:290 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] get_task_struct include/linux/sched/task.h:116 [inline] get_pid_task+0xbb/0x250 kernel/pid.c:472 get_proc_task fs/proc/internal.h:149 [inline] proc_pident_lookup+0x49/0x270 fs/proc/base.c:2715 lookup_open.isra.0+0x4e2/0x1780 fs/namei.c:4413 open_last_lookups fs/namei.c:4540 [inline] path_openat+0x12bb/0x3140 fs/namei.c:4784 do_filp_open+0x20b/0x470 fs/namei.c:4814 do_sys_openat2+0x11f/0x280 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 0 UID: 0 PID: 13215 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_irq_inversion_bug.part.0+0x212/0x270 kernel/locking/lockdep.c:4125 print_irq_inversion_bug kernel/locking/lockdep.c:4076 [inline] check_usage_forwards kernel/locking/lockdep.c:4158 [inline] mark_lock_irq kernel/locking/lockdep.c:4294 [inline] mark_lock+0x399/0x9f0 kernel/locking/lockdep.c:4753 mark_usage kernel/locking/lockdep.c:4642 [inline] __lock_acquire+0xc3d/0x22f0 kernel/locking/lockdep.c:5191 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x330 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:395 [inline] input_event+0x74/0xd0 drivers/input/input.c:391 input_report_key include/linux/input.h:439 [inline] pegasus_parse_packet drivers/input/tablet/pegasus_notetaker.c:163 [inline] pegasus_irq+0x42c/0x630 drivers/input/tablet/pegasus_notetaker.c:186 __usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745 dummy_timer+0x1809/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x219/0x8b0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7190 Code: df 55 65 48 8b 2d ac cb 44 08 53 48 89 eb 48 c1 eb 03 48 01 c3 bf 01 00 00 00 e8 5f 59 22 f6 e8 8a 65 5e f6 fb bf 01 00 00 00 3f 96 ff ff 9c 58 fa f6 c4 02 75 1e bf 01 00 00 00 e8 8d e7 21 RSP: 0018:ffffc9001406f768 EFLAGS: 00000202 RAX: 00000000000002c1 RBX: ffffed100f16b7a0 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffffffff8dabf2de RDI: 0000000000000001 RBP: ffff888078b5bd00 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff908786d7 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__refcount_add include/linux/refcount.h:290 [inline] RIP: 0010:__refcount_inc include/linux/refcount.h:366 [inline] RIP: 0010:refcount_inc include/linux/refcount.h:383 [inline] RIP: 0010:get_task_struct include/linux/sched/task.h:116 [inline] RIP: 0010:get_pid_task+0xbb/0x250 kernel/pid.c:472 Code: ab c8 38 00 85 ed 0f 84 77 01 00 00 e8 ee cd 38 00 31 ff 89 ee e8 95 c8 38 00 85 ed 0f 88 78 01 00 00 e8 d8 cd 38 00 83 c5 01 <31> ff 89 ee e8 7c c8 38 00 85 ed 0f 88 5f 01 00 00 e8 bf cd 38 00 RSP: 0018:ffffc9001406f878 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff888078b5bd00 RCX: ffffffff81856bdb RDX: ffff888078b5bd00 RSI: ffffffff81856be8 RDI: 0000000000000005 RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 000000001ae22cda R12: ffff888078b5bd28 R13: ffff888026e0e758 R14: ffffffff8ba39b10 R15: ffff888026e0e7c0 get_proc_task fs/proc/internal.h:149 [inline] proc_pident_lookup+0x49/0x270 fs/proc/base.c:2715 lookup_open.isra.0+0x4e2/0x1780 fs/namei.c:4413 open_last_lookups fs/namei.c:4540 [inline] path_openat+0x12bb/0x3140 fs/namei.c:4784 do_filp_open+0x20b/0x470 fs/namei.c:4814 do_sys_openat2+0x11f/0x280 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0d0d18df90 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 69 95 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 bc 95 02 00 8b 44 RSP: 002b:00007ffd28cb80d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007f0d0d18df90 RDX: 0000000000080001 RSI: 00007f0d0d2158aa RDI: 00000000ffffff9c RBP: 00007f0d0d2158aa R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004 R13: 00007ffd28cb8170 R14: 0000000000068740 R15: 00007ffd28cb86e0 usb 7-1: pegasus_irq - nonzero urb status received: -71 usb 7-1: pegasus_irq - nonzero urb status received: -71 usb 7-1: pegasus_irq - nonzero urb status received: -71 usb 7-1: pegasus_irq - urb shutting down with status: -2 ---------------- Code disassembly (best guess): 0: df 55 65 fists 0x65(%rbp) 3: 48 8b 2d ac cb 44 08 mov 0x844cbac(%rip),%rbp # 0x844cbb6 a: 53 push %rbx b: 48 89 eb mov %rbp,%rbx e: 48 c1 eb 03 shr $0x3,%rbx 12: 48 01 c3 add %rax,%rbx 15: bf 01 00 00 00 mov $0x1,%edi 1a: e8 5f 59 22 f6 call 0xf622597e 1f: e8 8a 65 5e f6 call 0xf65e65ae 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 3f 96 ff ff call 0xffff966e <-- trapping instruction 2f: 9c pushf 30: 58 pop %rax 31: fa cli 32: f6 c4 02 test $0x2,%ah 35: 75 1e jne 0x55 37: bf 01 00 00 00 mov $0x1,%edi 3c: e8 .byte 0xe8 3d: 8d (bad) 3e: e7 21 out %eax,$0x21