syzbot


possible deadlock in kbd_event

Status: upstream: reported on 2025/10/14 00:10
Subsystems: fs serial
[Documentation on labels]
Reported-by: syzbot+781c8bb5e4d62cc883d3@syzkaller.appspotmail.com
First crash: 209d, last: 12h27m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
6a5e4858-605f-4a7b-9c77-899114b2fd94 repro possible deadlock in kbd_event 2026/03/06 01:30 2026/03/06 01:30 2026/03/06 01:38 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Discussions (6)
Title Replies (including bot) Last reply
[syzbot] Monthly serial report (May 2026) 0 (1) 2026/05/02 20:32
[syzbot] Monthly serial report (Apr 2026) 0 (1) 2026/04/01 13:14
[syzbot] Monthly serial report (Nov 2025) 0 (1) 2025/11/27 12:43
[syzbot] Monthly kernfs report (Nov 2025) 0 (1) 2025/11/25 08:46
[syzbot] Monthly serial report (Oct 2025) 0 (1) 2025/10/27 05:54
[syzbot] [serial?] possible deadlock in kbd_event 0 (1) 2025/10/14 00:10

Sample crash report:
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
syzkaller #0 Tainted: G             L     
-----------------------------------------------------
syz.2.6005/28116 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffff88802ed75440 (&tty->flow.lock){....}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline]
ffff88802ed75440 (&tty->flow.lock){....}-{3:3}, at: stop_tty+0x2f/0x140 drivers/tty/tty_io.c:765

and this task is already holding:
ffffffff8f20ae18 (kbd_event_lock){..-.}-{3:3}, at: spin_lock include/linux/spinlock.h:342 [inline]
ffffffff8f20ae18 (kbd_event_lock){..-.}-{3:3}, at: class_spinlock_constructor include/linux/spinlock.h:587 [inline]
ffffffff8f20ae18 (kbd_event_lock){..-.}-{3:3}, at: kbd_event+0xd7/0x42f0 drivers/tty/vt/keyboard.c:1578
which would create a new lock dependency:
 (kbd_event_lock){..-.}-{3:3} -> (&tty->flow.lock){....}-{3:3}

but this new dependency connects a SOFTIRQ-irq-safe lock:
 (kbd_event_lock){..-.}-{3:3}

... which became SOFTIRQ-irq-safe at:
  lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
  __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
  _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158
  spin_lock include/linux/spinlock.h:342 [inline]
  class_spinlock_constructor include/linux/spinlock.h:587 [inline]
  kbd_event+0xd7/0x42f0 drivers/tty/vt/keyboard.c:1578
  input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2558
  input_pass_values+0x288/0x890 drivers/input/input.c:128
  input_event_dispose+0x3e5/0x6b0 drivers/input/input.c:353
  input_event+0x84/0xc0 drivers/input/input.c:396
  hidinput_hid_event+0x143a/0x1ec0 drivers/hid/hid-input.c:1762
  hid_process_event+0x4be/0x620 drivers/hid/hid-core.c:1576
  hid_process_report drivers/hid/hid-core.c:1724 [inline]
  hid_report_raw_event+0xec2/0x1730 drivers/hid/hid-core.c:2082
  __hid_input_report drivers/hid/hid-core.c:2152 [inline]
  hid_input_report+0x44b/0x580 drivers/hid/hid-core.c:2174
  hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286
  __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1657
  dummy_timer+0xbc0/0x4650 drivers/usb/gadget/udc/dummy_hcd.c:2005
  __run_hrtimer kernel/time/hrtimer.c:1930 [inline]
  __hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
  hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011
  handle_softirqs+0x22a/0x840 kernel/softirq.c:622
  __do_softirq kernel/softirq.c:656 [inline]
  invoke_softirq kernel/softirq.c:496 [inline]
  __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
  kasan_byte_accessible+0x16/0x30 mm/kasan/generic.c:210
  __kasan_check_byte+0x12/0x40 mm/kasan/common.c:573
  kasan_check_byte include/linux/kasan.h:402 [inline]
  lock_acquire+0x84/0x350 kernel/locking/lockdep.c:5842
  local_trylock_acquire include/linux/local_lock_internal.h:53 [inline]
  alloc_from_pcs mm/slub.c:4743 [inline]
  slab_alloc_node mm/slub.c:4883 [inline]
  __do_kmalloc_node mm/slub.c:5294 [inline]
  __kmalloc_noprof+0x1d4/0x760 mm/slub.c:5307
  kmalloc_noprof include/linux/slab.h:954 [inline]
  tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
  tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
  tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827
  tomoyo_path_unlink+0xaa/0xf0 security/tomoyo/tomoyo.c:162
  security_path_unlink+0x15f/0x330 security/security.c:1483
  filename_unlinkat+0x349/0x610 fs/namei.c:5565
  __do_sys_unlink fs/namei.c:5603 [inline]
  __se_sys_unlink+0x2e/0x140 fs/namei.c:5600
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
  entry_SYSCALL_64_after_hwframe+0x77/0x7f

to a SOFTIRQ-irq-unsafe lock:
 (tasklist_lock){.+.+}-{3:3}

... which became SOFTIRQ-irq-unsafe at:
...
  lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
  __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline]
  _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232
  __do_wait+0xde/0x740 kernel/exit.c:1677
  do_wait+0x1e7/0x510 kernel/exit.c:1721
  kernel_wait+0xd6/0x1c0 kernel/exit.c:1897
  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:3302 [inline]
  process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
  worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
  kthread+0x388/0x470 kernel/kthread.c:436
  ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

other info that might help us debug this:

Chain exists of:
  kbd_event_lock --> &tty->flow.lock --> tasklist_lock

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(tasklist_lock);
                               local_irq_disable();
                               lock(kbd_event_lock);
                               lock(&tty->flow.lock);
  <Interrupt>
    lock(kbd_event_lock);

 *** DEADLOCK ***

5 locks held by syz.2.6005/28116:
 #0: ffff88802ce45110 (&evdev->mutex){+.+.}-{4:4}, at: evdev_write+0x1ae/0x4c0 drivers/input/evdev.c:511
 #1: ffff88802cd6a230 (&dev->event_lock#2){..-.}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline]
 #1: ffff88802cd6a230 (&dev->event_lock#2){..-.}-{3:3}, at: input_inject_event+0xa4/0x330 drivers/input/input.c:419
 #2: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #2: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #2: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 #2: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: input_inject_event+0xb5/0x330 drivers/input/input.c:420
 #3: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #3: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #3: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 #3: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: input_pass_values+0x8d/0x890 drivers/input/input.c:119
 #4: ffffffff8f20ae18 (kbd_event_lock){..-.}-{3:3}, at: spin_lock include/linux/spinlock.h:342 [inline]
 #4: ffffffff8f20ae18 (kbd_event_lock){..-.}-{3:3}, at: class_spinlock_constructor include/linux/spinlock.h:587 [inline]
 #4: ffffffff8f20ae18 (kbd_event_lock){..-.}-{3:3}, at: kbd_event+0xd7/0x42f0 drivers/tty/vt/keyboard.c:1578

the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (kbd_event_lock){..-.}-{3:3} {
   IN-SOFTIRQ-W at:
                    lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                    __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
                    _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158
                    spin_lock include/linux/spinlock.h:342 [inline]
                    class_spinlock_constructor include/linux/spinlock.h:587 [inline]
                    kbd_event+0xd7/0x42f0 drivers/tty/vt/keyboard.c:1578
                    input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2558
                    input_pass_values+0x288/0x890 drivers/input/input.c:128
                    input_event_dispose+0x3e5/0x6b0 drivers/input/input.c:353
                    input_event+0x84/0xc0 drivers/input/input.c:396
                    hidinput_hid_event+0x143a/0x1ec0 drivers/hid/hid-input.c:1762
                    hid_process_event+0x4be/0x620 drivers/hid/hid-core.c:1576
                    hid_process_report drivers/hid/hid-core.c:1724 [inline]
                    hid_report_raw_event+0xec2/0x1730 drivers/hid/hid-core.c:2082
                    __hid_input_report drivers/hid/hid-core.c:2152 [inline]
                    hid_input_report+0x44b/0x580 drivers/hid/hid-core.c:2174
                    hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286
                    __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1657
                    dummy_timer+0xbc0/0x4650 drivers/usb/gadget/udc/dummy_hcd.c:2005
                    __run_hrtimer kernel/time/hrtimer.c:1930 [inline]
                    __hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
                    hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011
                    handle_softirqs+0x22a/0x840 kernel/softirq.c:622
                    __do_softirq kernel/softirq.c:656 [inline]
                    invoke_softirq kernel/softirq.c:496 [inline]
                    __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
                    irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
                    instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
                    sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
                    asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
                    kasan_byte_accessible+0x16/0x30 mm/kasan/generic.c:210
                    __kasan_check_byte+0x12/0x40 mm/kasan/common.c:573
                    kasan_check_byte include/linux/kasan.h:402 [inline]
                    lock_acquire+0x84/0x350 kernel/locking/lockdep.c:5842
                    local_trylock_acquire include/linux/local_lock_internal.h:53 [inline]
                    alloc_from_pcs mm/slub.c:4743 [inline]
                    slab_alloc_node mm/slub.c:4883 [inline]
                    __do_kmalloc_node mm/slub.c:5294 [inline]
                    __kmalloc_noprof+0x1d4/0x760 mm/slub.c:5307
                    kmalloc_noprof include/linux/slab.h:954 [inline]
                    tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
                    tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
                    tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827
                    tomoyo_path_unlink+0xaa/0xf0 security/tomoyo/tomoyo.c:162
                    security_path_unlink+0x15f/0x330 security/security.c:1483
                    filename_unlinkat+0x349/0x610 fs/namei.c:5565
                    __do_sys_unlink fs/namei.c:5603 [inline]
                    __se_sys_unlink+0x2e/0x140 fs/namei.c:5600
                    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
                    do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
                    entry_SYSCALL_64_after_hwframe+0x77/0x7f
   INITIAL USE at:
                   lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
                   _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
                   class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline]
                   vt_reset_unicode+0x2b/0x160 drivers/tty/vt/keyboard.c:2194
                   reset_vc+0x68/0x1b0 drivers/tty/vt/vt_ioctl.c:966
                   vc_init+0x70/0x4a0 drivers/tty/vt/vt.c:3823
                   con_init+0x377/0x6a0 drivers/tty/vt/vt.c:3889
                   console_init+0x10b/0x4a0 kernel/printk/printk.c:4407
                   start_kernel+0x230/0x3e0 init/main.c:1157
                   x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
                   x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
                   common_startup_64+0x13e/0x147
 }
 ... key      at: [<ffffffff8f20ae18>] kbd_event_lock+0x18/0xa0 keyboard.c:-1

the dependencies between the lock to be acquired
 and SOFTIRQ-irq-unsafe lock:
   -> (tasklist_lock){.+.+}-{3:3} {
      HARDIRQ-ON-R at:
                          lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                          __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline]
                          _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232
                          __do_wait+0xde/0x740 kernel/exit.c:1677
                          do_wait+0x1e7/0x510 kernel/exit.c:1721
                          kernel_wait+0xd6/0x1c0 kernel/exit.c:1897
                          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:3302 [inline]
                          process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
                          worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
                          kthread+0x388/0x470 kernel/kthread.c:436
                          ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
                          ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
      SOFTIRQ-ON-R at:
                          lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                          __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline]
                          _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232
                          __do_wait+0xde/0x740 kernel/exit.c:1677
                          do_wait+0x1e7/0x510 kernel/exit.c:1721
                          kernel_wait+0xd6/0x1c0 kernel/exit.c:1897
                          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:3302 [inline]
                          process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
                          worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
                          kthread+0x388/0x470 kernel/kthread.c:436
                          ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
                          ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
      INITIAL USE at:
                         lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                         __raw_write_lock_irq include/linux/rwlock_api_smp.h:213 [inline]
                         _raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:330
                         copy_process+0x2b4c/0x4440 kernel/fork.c:2411
                         kernel_clone+0x284/0x8f0 kernel/fork.c:2721
                         user_mode_thread+0x110/0x180 kernel/fork.c:2797
                         rest_init+0x23/0x300 init/main.c:727
                         start_kernel+0x38a/0x3e0 init/main.c:1220
                         x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
                         x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
                         common_startup_64+0x13e/0x147
      INITIAL READ USE at:
                              lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                              __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline]
                              _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232
                              __do_wait+0xde/0x740 kernel/exit.c:1677
                              do_wait+0x1e7/0x510 kernel/exit.c:1721
                              kernel_wait+0xd6/0x1c0 kernel/exit.c:1897
                              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:3302 [inline]
                              process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
                              worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
                              kthread+0x388/0x470 kernel/kthread.c:436
                              ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
                              ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
    }
    ... key      at: [<ffffffff8e60a058>] tasklist_lock+0x18/0x40
    ... acquired at:
   __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline]
   _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232
   send_sigurg+0x12b/0x420 fs/fcntl.c:978
   sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3672
   queue_oob+0x42c/0x4f0 net/unix/af_unix.c:2368
   unix_stream_sendmsg+0xcb1/0xe80 net/unix/af_unix.c:2502
   sock_sendmsg_nosec net/socket.c:787 [inline]
   __sock_sendmsg net/socket.c:802 [inline]
   ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
   ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
   __sys_sendmsg net/socket.c:2784 [inline]
   __do_sys_sendmsg net/socket.c:2789 [inline]
   __se_sys_sendmsg net/socket.c:2787 [inline]
   __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
   do_syscall_64+0x15f/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+0x106/0x350 kernel/locking/lockdep.c:5868
                       __raw_write_lock_irq include/linux/rwlock_api_smp.h:213 [inline]
                       _raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:330
                       __f_setown+0x67/0x370 fs/fcntl.c:136
                       generic_add_lease fs/locks.c:1924 [inline]
                       generic_setlease+0xacf/0xfd0 fs/locks.c:2000
                       do_fcntl_add_lease+0x35e/0x470 fs/locks.c:2102
                       fcntl_setlease+0x123/0x180 fs/locks.c:2127
                       do_fcntl+0x8b3/0x1a20 fs/fcntl.c:535
                       __do_sys_fcntl fs/fcntl.c:602 [inline]
                       __se_sys_fcntl+0xc8/0x150 fs/fcntl.c:587
                       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
                       do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
                       entry_SYSCALL_64_after_hwframe+0x77/0x7f
     INITIAL READ USE at:
                            lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                            __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline]
                            _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240
                            send_sigio+0x38/0x370 fs/fcntl.c:918
                            kill_fasync_rcu fs/fcntl.c:1144 [inline]
                            kill_fasync+0x24d/0x4d0 fs/fcntl.c:1159
                            lease_break_callback+0x26/0x30 fs/locks.c:577
                            __break_lease+0x81f/0x1ea0 fs/locks.c:1669
                            break_deleg include/linux/filelock.h:505 [inline]
                            try_break_deleg include/linux/filelock.h:524 [inline]
                            vfs_remove_acl+0x21c/0x830 fs/posix_acl.c:1237
                            removexattr fs/xattr.c:1027 [inline]
                            file_removexattr fs/xattr.c:1037 [inline]
                            path_removexattrat+0x4c4/0x750 fs/xattr.c:1086
                            __do_sys_fremovexattr fs/xattr.c:1112 [inline]
                            __se_sys_fremovexattr fs/xattr.c:1110 [inline]
                            __x64_sys_fremovexattr+0x62/0x70 fs/xattr.c:1110
                            do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
                            do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
                            entry_SYSCALL_64_after_hwframe+0x77/0x7f
   }
   ... key      at: [<ffffffff9a4bc880>] file_f_owner_allocate.__key+0x0/0x20
   ... acquired at:
   __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline]
   _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240
   send_sigio+0x38/0x370 fs/fcntl.c:918
   kill_fasync_rcu fs/fcntl.c:1144 [inline]
   kill_fasync+0x24d/0x4d0 fs/fcntl.c:1159
   lease_break_callback+0x26/0x30 fs/locks.c:577
   __break_lease+0x81f/0x1ea0 fs/locks.c:1669
   break_deleg include/linux/filelock.h:505 [inline]
   try_break_deleg include/linux/filelock.h:524 [inline]
   vfs_remove_acl+0x21c/0x830 fs/posix_acl.c:1237
   removexattr fs/xattr.c:1027 [inline]
   file_removexattr fs/xattr.c:1037 [inline]
   path_removexattrat+0x4c4/0x750 fs/xattr.c:1086
   __do_sys_fremovexattr fs/xattr.c:1112 [inline]
   __se_sys_fremovexattr fs/xattr.c:1110 [inline]
   __x64_sys_fremovexattr+0x62/0x70 fs/xattr.c:1110
   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
   do_syscall_64+0x15f/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+0x106/0x350 kernel/locking/lockdep.c:5868
                     __raw_write_lock_irq include/linux/rwlock_api_smp.h:213 [inline]
                     _raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:330
                     fasync_remove_entry+0xf1/0x1c0 fs/fcntl.c:1012
                     lease_modify+0x4f7/0x6c0 fs/locks.c:1514
                     locks_remove_lease fs/locks.c:2773 [inline]
                     locks_remove_file+0x5f0/0xf70 fs/locks.c:2798
                     __fput+0x3ae/0xa60 fs/file_table.c:502
                     task_work_run+0x1d9/0x270 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:67 [inline]
                     exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
                     __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
                     syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
                     syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
                     do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
                     entry_SYSCALL_64_after_hwframe+0x77/0x7f
    INITIAL READ USE at:
                          lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                          __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline]
                          _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240
                          kill_fasync_rcu fs/fcntl.c:1135 [inline]
                          kill_fasync+0x199/0x4d0 fs/fcntl.c:1159
                          lease_break_callback+0x26/0x30 fs/locks.c:577
                          __break_lease+0x81f/0x1ea0 fs/locks.c:1669
                          break_deleg include/linux/filelock.h:505 [inline]
                          try_break_deleg include/linux/filelock.h:524 [inline]
                          vfs_remove_acl+0x21c/0x830 fs/posix_acl.c:1237
                          removexattr fs/xattr.c:1027 [inline]
                          file_removexattr fs/xattr.c:1037 [inline]
                          path_removexattrat+0x4c4/0x750 fs/xattr.c:1086
                          __do_sys_fremovexattr fs/xattr.c:1112 [inline]
                          __se_sys_fremovexattr fs/xattr.c:1110 [inline]
                          __x64_sys_fremovexattr+0x62/0x70 fs/xattr.c:1110
                          do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
                          do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
                          entry_SYSCALL_64_after_hwframe+0x77/0x7f
  }
  ... key      at: [<ffffffff9a4bc8a0>] fasync_insert_entry.__key+0x0/0x20
  ... acquired at:
   __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline]
   _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240
   kill_fasync_rcu fs/fcntl.c:1135 [inline]
   kill_fasync+0x199/0x4d0 fs/fcntl.c:1159
   tty_wakeup drivers/tty/tty_io.c:515 [inline]
   __start_tty+0x18c/0x220 drivers/tty/tty_io.c:777
   start_tty drivers/tty/tty_io.c:794 [inline]
   tty_send_xchar+0x1cf/0x4b0 drivers/tty/tty_io.c:1153
   tty_ioctl+0x9c5/0xde0 drivers/tty/tty_io.c:2801
   vfs_ioctl fs/ioctl.c:51 [inline]
   __do_sys_ioctl fs/ioctl.c:597 [inline]
   __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
   do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> (&tty->flow.lock){....}-{3:3} {
   INITIAL USE at:
                   lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
                   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
                   _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
                   class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline]
                   start_tty+0x1b/0x50 drivers/tty/tty_io.c:793
                   n_tty_set_termios+0xa7c/0x10a0 drivers/tty/n_tty.c:1848
                   tty_set_termios+0xdb3/0x1800 drivers/tty/tty_ioctl.c:348
                   set_termios+0x566/0x710 drivers/tty/tty_ioctl.c:516
                   tty_mode_ioctl+0x4a6/0x7d0 drivers/tty/tty_ioctl.c:-1
                   tty_ioctl+0x9c5/0xde0 drivers/tty/tty_io.c:2801
                   vfs_ioctl fs/ioctl.c:51 [inline]
                   __do_sys_ioctl fs/ioctl.c:597 [inline]
                   __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
                   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
                   do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
                   entry_SYSCALL_64_after_hwframe+0x77/0x7f
 }
 ... key      at: [<ffffffff9a79c5e0>] alloc_tty_struct.__key.35+0x0/0x20
 ... acquired at:
   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
   _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
   class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline]
   stop_tty+0x2f/0x140 drivers/tty/tty_io.c:765
   kbd_keycode drivers/tty/vt/keyboard.c:1565 [inline]
   kbd_event+0x2f91/0x42f0 drivers/tty/vt/keyboard.c:1583
   input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2558
   input_pass_values+0x288/0x890 drivers/input/input.c:128
   input_event_dispose+0x330/0x6b0 drivers/input/input.c:342
   input_inject_event+0x1dc/0x330 drivers/input/input.c:424
   evdev_write+0x325/0x4c0 drivers/input/evdev.c:528
   vfs_write+0x29a/0xb90 fs/read_write.c:686
   ksys_write+0x150/0x270 fs/read_write.c:740
   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
   do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
   entry_SYSCALL_64_after_hwframe+0x77/0x7f


stack backtrace:
CPU: 1 UID: 0 PID: 28116 Comm: syz.2.6005 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_bad_irq_dependency kernel/locking/lockdep.c:2616 [inline]
 check_irq_usage kernel/locking/lockdep.c:2857 [inline]
 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+0x2a94/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
 class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline]
 stop_tty+0x2f/0x140 drivers/tty/tty_io.c:765
 kbd_keycode drivers/tty/vt/keyboard.c:1565 [inline]
 kbd_event+0x2f91/0x42f0 drivers/tty/vt/keyboard.c:1583
 input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2558
 input_pass_values+0x288/0x890 drivers/input/input.c:128
 input_event_dispose+0x330/0x6b0 drivers/input/input.c:342
 input_inject_event+0x1dc/0x330 drivers/input/input.c:424
 evdev_write+0x325/0x4c0 drivers/input/evdev.c:528
 vfs_write+0x29a/0xb90 fs/read_write.c:686
 ksys_write+0x150/0x270 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f236979cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f236a5ac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f2369a15fa0 RCX: 00007f236979cdd9
RDX: 0000000000002250 RSI: 0000200000000040 RDI: 0000000000000008
RBP: 00007f2369832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2369a16038 R14: 00007f2369a15fa0 R15: 00007f2369b3fa48
 </TASK>

Crashes (182):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/07 04:03 upstream 74fe02ce122a cbcd9ea0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/05/04 10:29 upstream 6d35786de281 85f1bcf2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/05/03 19:11 upstream f377d0025eb0 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/05/03 15:40 upstream 66edb901bf87 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/05/03 01:53 upstream 66edb901bf87 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/23 00:26 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/22 10:52 upstream 6596a02b2078 4595e353 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/20 21:00 upstream a5d1079c28a5 e65da4ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/20 16:10 upstream c1f49dea2b8f e65da4ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/20 01:38 upstream c1f49dea2b8f 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/19 12:31 upstream faeab166167f 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/18 22:24 upstream eb5249b12507 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/18 16:23 upstream 8541d8f725c6 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/18 07:57 upstream 8541d8f725c6 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/18 06:25 upstream 8541d8f725c6 5be7a9de .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/17 17:59 upstream 43cfbdda5af6 24ecfc1e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/16 17:00 upstream 1d51b370a0f8 321ae225 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/15 15:01 upstream 1f5ffc672165 c441f497 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/13 10:50 upstream 028ef9c96e96 9530ccf9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/13 02:37 upstream 028ef9c96e96 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/10 09:42 upstream 9a9c8ce300cd 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/09 17:44 upstream 8b02520ec5f7 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/06 10:02 upstream 591cd656a1bf 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/06 07:02 upstream 1791c390149f 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/04 10:54 upstream 7ca6d1cfec80 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/31 13:52 upstream d0c3bcd5b897 aeea1c72 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/30 17:03 upstream 7aaa8047eafd 458630d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/27 20:02 upstream 46b513250491 74a13a23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/26 06:45 upstream d2a43e7f89da c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/21 08:08 upstream c612261bedd6 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/15 06:50 upstream 69237f8c1f69 ee8d34d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/12 23:45 upstream 0257f64bdac7 2f7f359d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/12 10:37 upstream 80234b5ab240 4efadf07 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/11 00:56 upstream b4f0dd314b39 4683d576 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/10 21:06 upstream 1f318b96cc84 4683d576 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/04 11:36 upstream 0031c06807cf e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/03/03 13:54 upstream af4e9ef3d784 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/02/28 20:25 upstream 9197e5949a41 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/02/26 13:49 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/02/20 17:24 upstream 8bf22c33e7a1 741f5161 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in kbd_event
2026/02/18 18:31 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/02/09 11:26 upstream 05f7e89ab973 df949cd9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/02/08 17:12 upstream e7aa57247700 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/02/02 11:10 upstream 18f7fcd5e69a 018ebef2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/01/18 06:48 upstream e84d960149e7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/01/15 22:20 upstream 944aacb68baf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in kbd_event
2025/10/13 18:09 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2025/10/10 00:07 upstream 18a7e218cfcd 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce possible deadlock in kbd_event
2026/04/07 21:30 upstream 3036cd0d3328 628666c6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 possible deadlock in kbd_event
2026/01/20 00:38 linux-next d08c85ac8894 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce possible deadlock in kbd_event
2025/10/10 07:40 linux-next 0b2f041c47ac ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in kbd_event
* Struck through repros no longer work on HEAD.