possible deadlock in input_event

Status: upstream: reported C repro on 2025/06/30 21:29
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+1b21cb06d4cb066076cd@syzkaller.appspotmail.com
First crash: 403d, last: 68d
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/11/21 linux-6.6.y (ToT) 0a805b6ea8cd C [report] possible deadlock in input_event
2025/11/21 upstream (ToT) fd95357fd8c6 C Didn't crash
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in input_event origin:upstream missing-backport 4 syz, C done 553 70d 1141d 0/3 upstream: reported C repro on 2023/06/23 12:11
upstream possible deadlock in input_event (2) fs 4 syz, C inconclusive 7546 23d 1731d 0/29 upstream: reported C repro on 2021/11/10 17:01
upstream possible deadlock in input_event 4 syz, C done 2740 1732d 2036d 0/29 closed as dup on 2021/07/07 07:31
linux-5.15 possible deadlock in input_event missing-backport origin:upstream 4 syz, C done 554 51d 1117d 2/3 upstream: reported C repro on 2023/07/17 14:44
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2026/01/02 05:02 1h30m fix candidate upstream OK (0) job log

Sample crash report:
=====================================================
WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
syzkaller #0 Not tainted
-----------------------------------------------------
syz.0.17/5952 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffff88802f513a18 (&f->f_owner.lock){....}-{2:2}, at: send_sigio+0x33/0x360 fs/fcntl.c:772

and this task is already holding:
ffff888024652018 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:990 [inline]
ffff888024652018 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
which would create a new lock dependency:
 (&new->fa_lock){....}-{2:2} -> (&f->f_owner.lock){....}-{2:2}

but this new dependency connects a HARDIRQ-irq-safe lock:
 (&dev->event_lock#2){-...}-{2:2}

... which became HARDIRQ-irq-safe at:
  lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
  __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
  _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
  input_event+0x7a/0xc0 drivers/input/input.c:434
  input_report_key include/linux/input.h:425 [inline]
  psmouse_report_standard_buttons drivers/input/mouse/psmouse-base.c:128 [inline]
  psmouse_report_standard_packet+0x53/0x200 drivers/input/mouse/psmouse-base.c:146
  psmouse_process_byte+0x478/0x670 drivers/input/mouse/psmouse-base.c:237
  psmouse_handle_byte+0x43/0x490 drivers/input/mouse/psmouse-base.c:279
  ps2_interrupt+0x164/0x980 drivers/input/serio/libps2.c:613
  serio_interrupt+0x8b/0x130 drivers/input/serio/serio.c:998
  i8042_interrupt+0x394/0x730 drivers/input/serio/i8042.c:610
  __handle_irq_event_percpu+0x276/0x930 kernel/irq/handle.c:158
  handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
  handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210
  handle_edge_irq+0x247/0xb30 kernel/irq/chip.c:831
  generic_handle_irq_desc include/linux/irqdesc.h:161 [inline]
  handle_irq arch/x86/kernel/irq.c:240 [inline]
  __common_interrupt+0x13b/0x230 arch/x86/kernel/irq.c:259
  common_interrupt+0xb4/0xd0 arch/x86/kernel/irq.c:249
  asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:678
  __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
  _raw_spin_unlock_irqrestore+0xa9/0x110 kernel/locking/spinlock.c:194
  spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
  i8042_command drivers/input/serio/i8042.c:360 [inline]
  i8042_aux_write+0x109/0x170 drivers/input/serio/i8042.c:395
  serio_write include/linux/serio.h:126 [inline]
  ps2_do_sendbyte+0x1ff/0x6d0 drivers/input/serio/libps2.c:58
  ps2_sendbyte+0x5f/0x120 drivers/input/serio/libps2.c:113
  cypress_ps2_sendbyte drivers/input/mouse/cypress_ps2.c:42 [inline]
  cypress_ps2_read_cmd_status drivers/input/mouse/cypress_ps2.c:116 [inline]
  cypress_send_ext_cmd+0x23d/0x920 drivers/input/mouse/cypress_ps2.c:189
  cypress_detect+0x8d/0x190 drivers/input/mouse/cypress_ps2.c:205
  psmouse_do_detect drivers/input/mouse/psmouse-base.c:1006 [inline]
  psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1020 [inline]
  psmouse_extensions+0x467/0xbe0 drivers/input/mouse/psmouse-base.c:1143
  psmouse_switch_protocol+0xdc/0x610 drivers/input/mouse/psmouse-base.c:1537
  psmouse_connect+0x89f/0x1470 drivers/input/mouse/psmouse-base.c:1626
  serio_connect_driver drivers/input/serio/serio.c:44 [inline]
  serio_driver_probe+0x7a/0xa0 drivers/input/serio/serio.c:775
  call_driver_probe drivers/base/dd.c:-1 [inline]
  really_probe+0x25b/0xb40 drivers/base/dd.c:658
  __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
  driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
  __driver_attach+0x44e/0x6f0 drivers/base/dd.c:1216
  bus_for_each_dev+0x22d/0x2a0 drivers/base/bus.c:370
  serio_attach_driver drivers/input/serio/serio.c:804 [inline]
  serio_handle_event+0x1a2/0x860 drivers/input/serio/serio.c:224
  process_one_work kernel/workqueue.c:2634 [inline]
  process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
  worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
  kthread+0x2fa/0x390 kernel/kthread.c:388
  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
  ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

to a HARDIRQ-irq-unsafe lock:
 (tasklist_lock){.+.+}-{2:2}

... which became HARDIRQ-irq-unsafe at:
...
  lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
  __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
  _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
  do_wait+0x294/0xaf0 kernel/exit.c:1607
  kernel_wait+0xac/0x170 kernel/exit.c:1797
  call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
  call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
  process_one_work kernel/workqueue.c:2634 [inline]
  process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
  worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
  kthread+0x2fa/0x390 kernel/kthread.c:388
  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
  ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

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);
  <Interrupt>
    lock(&dev->event_lock#2);

 *** DEADLOCK ***

8 locks held by syz.0.17/5952:
 #0: ffff888025fe2110 (&evdev->mutex){+.+.}-{3:3}, at: evdev_write+0x17b/0x470 drivers/input/evdev.c:513
 #1: ffff888142afc230 (&dev->event_lock#2){-...}-{2:2}, at: input_inject_event+0xab/0x320 drivers/input/input.c:460
 #2: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #2: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #2: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: input_inject_event+0xbc/0x320 drivers/input/input.c:462
 #3: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #3: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #3: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: input_pass_values+0xa3/0x1300 drivers/input/input.c:153
 #4: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #4: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #4: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: evdev_events+0x79/0x330 drivers/input/evdev.c:298
 #5: ffff88802c574028 (&client->buffer_lock){....}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #5: ffff88802c574028 (&client->buffer_lock){....}-{2:2}, at: evdev_pass_values+0xcb/0xab0 drivers/input/evdev.c:261
 #6: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #6: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #6: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x53/0x4b0 fs/fcntl.c:1010
 #7: ffff888024652018 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:990 [inline]
 #7: ffff888024652018 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x192/0x4b0 fs/fcntl.c:1011

the dependencies between HARDIRQ-irq-safe lock and the holding lock:
  -> (&dev->event_lock#2){-...}-{2:2} {
     IN-HARDIRQ-W at:
                        lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                        __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                        _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
                        input_event+0x7a/0xc0 drivers/input/input.c:434
                        input_report_key include/linux/input.h:425 [inline]
                        psmouse_report_standard_buttons drivers/input/mouse/psmouse-base.c:128 [inline]
                        psmouse_report_standard_packet+0x53/0x200 drivers/input/mouse/psmouse-base.c:146
                        psmouse_process_byte+0x478/0x670 drivers/input/mouse/psmouse-base.c:237
                        psmouse_handle_byte+0x43/0x490 drivers/input/mouse/psmouse-base.c:279
                        ps2_interrupt+0x164/0x980 drivers/input/serio/libps2.c:613
                        serio_interrupt+0x8b/0x130 drivers/input/serio/serio.c:998
                        i8042_interrupt+0x394/0x730 drivers/input/serio/i8042.c:610
                        __handle_irq_event_percpu+0x276/0x930 kernel/irq/handle.c:158
                        handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
                        handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210
                        handle_edge_irq+0x247/0xb30 kernel/irq/chip.c:831
                        generic_handle_irq_desc include/linux/irqdesc.h:161 [inline]
                        handle_irq arch/x86/kernel/irq.c:240 [inline]
                        __common_interrupt+0x13b/0x230 arch/x86/kernel/irq.c:259
                        common_interrupt+0xb4/0xd0 arch/x86/kernel/irq.c:249
                        asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:678
                        __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
                        _raw_spin_unlock_irqrestore+0xa9/0x110 kernel/locking/spinlock.c:194
                        spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
                        i8042_command drivers/input/serio/i8042.c:360 [inline]
                        i8042_aux_write+0x109/0x170 drivers/input/serio/i8042.c:395
                        serio_write include/linux/serio.h:126 [inline]
                        ps2_do_sendbyte+0x1ff/0x6d0 drivers/input/serio/libps2.c:58
                        ps2_sendbyte+0x5f/0x120 drivers/input/serio/libps2.c:113
                        cypress_ps2_sendbyte drivers/input/mouse/cypress_ps2.c:42 [inline]
                        cypress_ps2_read_cmd_status drivers/input/mouse/cypress_ps2.c:116 [inline]
                        cypress_send_ext_cmd+0x23d/0x920 drivers/input/mouse/cypress_ps2.c:189
                        cypress_detect+0x8d/0x190 drivers/input/mouse/cypress_ps2.c:205
                        psmouse_do_detect drivers/input/mouse/psmouse-base.c:1006 [inline]
                        psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1020 [inline]
                        psmouse_extensions+0x467/0xbe0 drivers/input/mouse/psmouse-base.c:1143
                        psmouse_switch_protocol+0xdc/0x610 drivers/input/mouse/psmouse-base.c:1537
                        psmouse_connect+0x89f/0x1470 drivers/input/mouse/psmouse-base.c:1626
                        serio_connect_driver drivers/input/serio/serio.c:44 [inline]
                        serio_driver_probe+0x7a/0xa0 drivers/input/serio/serio.c:775
                        call_driver_probe drivers/base/dd.c:-1 [inline]
                        really_probe+0x25b/0xb40 drivers/base/dd.c:658
                        __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
                        driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
                        __driver_attach+0x44e/0x6f0 drivers/base/dd.c:1216
                        bus_for_each_dev+0x22d/0x2a0 drivers/base/bus.c:370
                        serio_attach_driver drivers/input/serio/serio.c:804 [inline]
                        serio_handle_event+0x1a2/0x860 drivers/input/serio/serio.c:224
                        process_one_work kernel/workqueue.c:2634 [inline]
                        process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
                        worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
                        kthread+0x2fa/0x390 kernel/kthread.c:388
                        ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
                        ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
     INITIAL USE at:
                       lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                       _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
                       input_inject_event+0xab/0x320 drivers/input/input.c:460
                       led_trigger_event+0x133/0x210 drivers/leds/led-triggers.c:393
                       kbd_led_trigger_activate+0xbd/0x100 drivers/tty/vt/keyboard.c:1036
                       led_trigger_set+0x524/0x940 drivers/leds/led-triggers.c:212
                       led_trigger_set_default+0x1a0/0x1e0 drivers/leds/led-triggers.c:276
                       led_classdev_register_ext+0x6e9/0x940 drivers/leds/led-class.c:562
                       led_classdev_register include/linux/leds.h:279 [inline]
                       input_leds_connect+0x4eb/0x6b0 drivers/input/input-leds.c:139
                       input_attach_handler drivers/input/input.c:1064 [inline]
                       input_register_device+0xcdc/0x1070 drivers/input/input.c:2470
                       atkbd_connect+0x6fb/0x9a0 drivers/input/keyboard/atkbd.c:1342
                       serio_connect_driver drivers/input/serio/serio.c:44 [inline]
                       serio_driver_probe+0x7a/0xa0 drivers/input/serio/serio.c:775
                       call_driver_probe drivers/base/dd.c:-1 [inline]
                       really_probe+0x25b/0xb40 drivers/base/dd.c:658
                       __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
                       driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
                       __driver_attach+0x44e/0x6f0 drivers/base/dd.c:1216
                       bus_for_each_dev+0x22d/0x2a0 drivers/base/bus.c:370
                       serio_attach_driver drivers/input/serio/serio.c:804 [inline]
                       serio_handle_event+0x1a2/0x860 drivers/input/serio/serio.c:224
                       process_one_work kernel/workqueue.c:2634 [inline]
                       process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
                       worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
                       kthread+0x2fa/0x390 kernel/kthread.c:388
                       ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
                       ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
   }
   ... key      at: [<ffffffff97213660>] input_allocate_device.__key.5+0x0/0x20
 -> (&client->buffer_lock){....}-{2:2} {
    INITIAL USE at:
                     lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                     __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+0xcb/0xab0 drivers/input/evdev.c:261
                     evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
                     input_to_handler drivers/input/input.c:129 [inline]
                     input_pass_values+0x907/0x1300 drivers/input/input.c:161
                     input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
                     input_inject_event+0x1f9/0x320 drivers/input/input.c:465
                     evdev_write+0x32a/0x470 drivers/input/evdev.c:530
                     vfs_write+0x288/0x940 fs/read_write.c:582
                     ksys_write+0x147/0x250 fs/read_write.c:637
                     do_syscall_x64 arch/x86/entry/common.c:51 [inline]
                     do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
                     entry_SYSCALL_64_after_hwframe+0x68/0xd2
  }
  ... key      at: [<ffffffff97213900>] evdev_open.__key.28+0x0/0x20
  ... 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+0xcb/0xab0 drivers/input/evdev.c:261
   evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
   input_to_handler drivers/input/input.c:129 [inline]
   input_pass_values+0x907/0x1300 drivers/input/input.c:161
   input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
   input_inject_event+0x1f9/0x320 drivers/input/input.c:465
   evdev_write+0x32a/0x470 drivers/input/evdev.c:530
   vfs_write+0x288/0x940 fs/read_write.c:582
   ksys_write+0x147/0x250 fs/read_write.c:637
   do_syscall_x64 arch/x86/entry/common.c:51 [inline]
   do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
   entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> (&new->fa_lock){....}-{2:2} {
   INITIAL READ USE at:
                        lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                        __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
                        _raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
                        kill_fasync_rcu fs/fcntl.c:990 [inline]
                        kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
                        __pass_event drivers/input/evdev.c:240 [inline]
                        evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278
                        evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
                        input_to_handler drivers/input/input.c:129 [inline]
                        input_pass_values+0x907/0x1300 drivers/input/input.c:161
                        input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
                        input_inject_event+0x1f9/0x320 drivers/input/input.c:465
                        evdev_write+0x32a/0x470 drivers/input/evdev.c:530
                        vfs_write+0x288/0x940 fs/read_write.c:582
                        ksys_write+0x147/0x250 fs/read_write.c:637
                        do_syscall_x64 arch/x86/entry/common.c:51 [inline]
                        do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
                        entry_SYSCALL_64_after_hwframe+0x68/0xd2
 }
 ... key      at: [<ffffffff96f1ab00>] fasync_insert_entry.__key+0x0/0x20
 ... acquired at:
   __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
   _raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
   kill_fasync_rcu fs/fcntl.c:990 [inline]
   kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
   __pass_event drivers/input/evdev.c:240 [inline]
   evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278
   evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
   input_to_handler drivers/input/input.c:129 [inline]
   input_pass_values+0x907/0x1300 drivers/input/input.c:161
   input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
   input_inject_event+0x1f9/0x320 drivers/input/input.c:465
   evdev_write+0x32a/0x470 drivers/input/evdev.c:530
   vfs_write+0x288/0x940 fs/read_write.c:582
   ksys_write+0x147/0x250 fs/read_write.c:637
   do_syscall_x64 arch/x86/entry/common.c:51 [inline]
   do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
   entry_SYSCALL_64_after_hwframe+0x68/0xd2


the dependencies between the lock to be acquired
 and HARDIRQ-irq-unsafe lock:
 -> (tasklist_lock){.+.+}-{2:2} {
    HARDIRQ-ON-R at:
                      lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                      __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
                      _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
                      do_wait+0x294/0xaf0 kernel/exit.c:1607
                      kernel_wait+0xac/0x170 kernel/exit.c:1797
                      call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
                      call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
                      process_one_work kernel/workqueue.c:2634 [inline]
                      process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
                      worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
                      kthread+0x2fa/0x390 kernel/kthread.c:388
                      ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
                      ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
    SOFTIRQ-ON-R at:
                      lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                      __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
                      _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
                      do_wait+0x294/0xaf0 kernel/exit.c:1607
                      kernel_wait+0xac/0x170 kernel/exit.c:1797
                      call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
                      call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
                      process_one_work kernel/workqueue.c:2634 [inline]
                      process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
                      worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
                      kthread+0x2fa/0x390 kernel/kthread.c:388
                      ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
                      ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
    INITIAL USE at:
                     lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                     __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
                     _raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
                     copy_process+0x225d/0x3d70 kernel/fork.c:2631
                     kernel_clone+0x21b/0x840 kernel/fork.c:2914
                     user_mode_thread+0xde/0x130 kernel/fork.c:2992
                     rest_init+0x27/0x300 init/main.c:709
                     arch_call_rest_init+0xe/0x10 init/main.c:841
                     start_kernel+0x459/0x4e0 init/main.c:1086
                     x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
                     copy_bootdata+0x0/0xe0 arch/x86/kernel/head64.c:536
                     secondary_startup_64_no_verify+0x179/0x17b
    INITIAL READ USE at:
                          lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                          __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
                          _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
                          do_wait+0x294/0xaf0 kernel/exit.c:1607
                          kernel_wait+0xac/0x170 kernel/exit.c:1797
                          call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
                          call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
                          process_one_work kernel/workqueue.c:2634 [inline]
                          process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
                          worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
                          kthread+0x2fa/0x390 kernel/kthread.c:388
                          ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
                          ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
  }
  ... key      at: [<ffffffff8ca0a058>] tasklist_lock+0x18/0x40
  ... acquired at:
   __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
   _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
   send_sigurg+0xf0/0x3c0 fs/fcntl.c:827
   sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3409
   queue_oob+0x3d7/0x4e0 net/unix/af_unix.c:2207
   unix_stream_sendmsg+0xaa2/0xba0 net/unix/af_unix.c:2326
   sock_sendmsg_nosec net/socket.c:730 [inline]
   __sock_sendmsg net/socket.c:745 [inline]
   ____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
   ___sys_sendmsg+0x220/0x290 net/socket.c:2649
   __sys_sendmmsg+0x275/0x4a0 net/socket.c:2735
   __do_sys_sendmmsg net/socket.c:2764 [inline]
   __se_sys_sendmmsg net/socket.c:2761 [inline]
   __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
   do_syscall_x64 arch/x86/entry/common.c:51 [inline]
   do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
   entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> (&f->f_owner.lock){....}-{2:2} {
   INITIAL USE at:
                   lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                   __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
                   _raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
                   __f_setown+0x3b/0x330 fs/fcntl.c:92
                   f_setown_ex fs/fcntl.c:195 [inline]
                   do_fcntl+0x10df/0x1380 fs/fcntl.c:377
                   __do_sys_fcntl fs/fcntl.c:448 [inline]
                   __se_sys_fcntl+0xc9/0x1a0 fs/fcntl.c:433
                   do_syscall_x64 arch/x86/entry/common.c:51 [inline]
                   do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
                   entry_SYSCALL_64_after_hwframe+0x68/0xd2
   INITIAL READ USE at:
                        lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
                        __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
                        _raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
                        send_sigurg+0x29/0x3c0 fs/fcntl.c:811
                        sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3409
                        queue_oob+0x3d7/0x4e0 net/unix/af_unix.c:2207
                        unix_stream_sendmsg+0xaa2/0xba0 net/unix/af_unix.c:2326
                        sock_sendmsg_nosec net/socket.c:730 [inline]
                        __sock_sendmsg net/socket.c:745 [inline]
                        ____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
                        ___sys_sendmsg+0x220/0x290 net/socket.c:2649
                        __sys_sendmmsg+0x275/0x4a0 net/socket.c:2735
                        __do_sys_sendmmsg net/socket.c:2764 [inline]
                        __se_sys_sendmmsg net/socket.c:2761 [inline]
                        __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
                        do_syscall_x64 arch/x86/entry/common.c:51 [inline]
                        do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
                        entry_SYSCALL_64_after_hwframe+0x68/0xd2
 }
 ... key      at: [<ffffffff96f19e80>] init_file.__key+0x0/0x20
 ... acquired at:
   __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
   _raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
   send_sigio+0x33/0x360 fs/fcntl.c:772
   kill_fasync_rcu fs/fcntl.c:997 [inline]
   kill_fasync+0x228/0x4b0 fs/fcntl.c:1011
   __pass_event drivers/input/evdev.c:240 [inline]
   evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278
   evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
   input_to_handler drivers/input/input.c:129 [inline]
   input_pass_values+0x907/0x1300 drivers/input/input.c:161
   input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
   input_inject_event+0x1f9/0x320 drivers/input/input.c:465
   evdev_write+0x32a/0x470 drivers/input/evdev.c:530
   vfs_write+0x288/0x940 fs/read_write.c:582
   ksys_write+0x147/0x250 fs/read_write.c:637
   do_syscall_x64 arch/x86/entry/common.c:51 [inline]
   do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
   entry_SYSCALL_64_after_hwframe+0x68/0xd2


stack backtrace:
CPU: 1 PID: 5952 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline]
 check_irq_usage kernel/locking/lockdep.c:2865 [inline]
 check_prev_add kernel/locking/lockdep.c:3138 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x678f/0x7c80 kernel/locking/lockdep.c:5137
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
 _raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
 send_sigio+0x33/0x360 fs/fcntl.c:772
 kill_fasync_rcu fs/fcntl.c:997 [inline]
 kill_fasync+0x228/0x4b0 fs/fcntl.c:1011
 __pass_event drivers/input/evdev.c:240 [inline]
 evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278
 evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
 input_to_handler drivers/input/input.c:129 [inline]
 input_pass_values+0x907/0x1300 drivers/input/input.c:161
 input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
 input_inject_event+0x1f9/0x320 drivers/input/input.c:465
 evdev_write+0x32a/0x470 drivers/input/evdev.c:530
 vfs_write+0x288/0x940 fs/read_write.c:582
 ksys_write+0x147/0x250 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7e0978f749
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:00007ffe3d7ce5f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7e099e5fa0 RCX: 00007f7e0978f749
RDX: 0000000000001068 RSI: 0000200000000040 RDI: 0000000000000006
RBP: 00007f7e09813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7e099e5fa0 R14: 00007f7e099e5fa0 R15: 0000000000000003
 </TASK>

Crashes (176):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/21 04:52 linux-6.6.y 0a805b6ea8cd 2cc4c24a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/06/01 05:31 linux-6.6.y 0a40c6fbd105 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/29 14:58 linux-6.6.y 0a40c6fbd105 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/27 14:47 linux-6.6.y 0a40c6fbd105 8777bdc3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/27 00:23 linux-6.6.y 0a40c6fbd105 2b01f00e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/26 11:43 linux-6.6.y 0a40c6fbd105 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/23 22:59 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/08 16:34 linux-6.6.y 3b9f64db0496 b2988c17 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/07 15:47 linux-6.6.y 258cf62a6dfd cbf9e0fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/06 15:22 linux-6.6.y 258cf62a6dfd 1dddfd3d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/04 23:47 linux-6.6.y 258cf62a6dfd a898ba9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/04 11:29 linux-6.6.y 258cf62a6dfd 85f1bcf2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/01 07:52 linux-6.6.y 258cf62a6dfd 753c55b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/05/01 05:41 linux-6.6.y 258cf62a6dfd 753c55b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/30 00:28 linux-6.6.y 142cd8382222 005438fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/29 12:11 linux-6.6.y 142cd8382222 7ca9e4d8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/27 18:43 linux-6.6.y 142cd8382222 0f700595 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/23 01:32 linux-6.6.y 9760bf04666d b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/18 13:42 linux-6.6.y 9760bf04666d 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/18 13:42 linux-6.6.y 9760bf04666d 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/18 06:23 linux-6.6.y 8cee53b8eaeb 5be7a9de .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/17 18:14 linux-6.6.y 8cee53b8eaeb 24ecfc1e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/17 03:06 linux-6.6.y 8cee53b8eaeb de0a551d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/16 02:51 linux-6.6.y 8cee53b8eaeb df15c5f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/14 16:23 linux-6.6.y 8cee53b8eaeb 362d1323 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/04/13 06:02 linux-6.6.y 8cee53b8eaeb 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/28 05:09 linux-6.6.y c09fbcd31ae6 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/28 05:08 linux-6.6.y c09fbcd31ae6 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/25 19:41 linux-6.6.y c09fbcd31ae6 8ee77f7d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/23 16:02 linux-6.6.y 4fc00fe35d46 4933dba2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/22 20:29 linux-6.6.y 4fc00fe35d46 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/19 13:16 linux-6.6.y 4fc00fe35d46 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/18 01:45 linux-6.6.y 4fc00fe35d46 c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/17 14:09 linux-6.6.y 4fc00fe35d46 c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/17 10:39 linux-6.6.y 4fc00fe35d46 c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/16 22:08 linux-6.6.y 4fc00fe35d46 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/11 19:31 linux-6.6.y 4fc00fe35d46 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/11 16:38 linux-6.6.y 4fc00fe35d46 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/11 04:39 linux-6.6.y 4fc00fe35d46 86914af9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/09 07:17 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/07 01:49 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/06 08:03 linux-6.6.y 4fc00fe35d46 31e9c887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/05 17:37 linux-6.6.y 4fc00fe35d46 d20b04c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/05 13:47 linux-6.6.y 682d8e2f892b d20b04c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2026/03/05 01:47 linux-6.6.y 682d8e2f892b a9fe5c9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
2025/06/30 21:29 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in input_event
* Struck through repros no longer work on HEAD.