| Title | Replies (including bot) | Last reply |
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| [syzbot] [serial?] possible deadlock in stop_tty | 0 (1) | 2025/11/04 03:59 |
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| [syzbot] [serial?] possible deadlock in stop_tty | 0 (1) | 2025/11/04 03:59 |
UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy
misc raw-gadget: fail, usb_gadget_register_driver returned -16
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
syzkaller #0 Tainted: G L
-----------------------------------------------------
syz.8.9383/1583 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffffffff8e20c058 (tasklist_lock){.+.+}-{3:3}, at: send_sigurg+0x12b/0x420 fs/fcntl.c:978
and this task is already holding:
ffff888029bd5720 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x55/0x420 fs/fcntl.c:962
which would create a new lock dependency:
(&f_owner->lock){....}-{3:3} -> (tasklist_lock){.+.+}-{3:3}
but this new dependency connects a SOFTIRQ-irq-safe lock:
(&tty->flow.lock){..-.}-{3:3}
... which became SOFTIRQ-irq-safe at:
lock_acquire+0x106/0x330 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:162
class_spinlock_irqsave_constructor include/linux/spinlock.h:617 [inline]
stop_tty+0x2f/0x150 drivers/tty/tty_io.c:765
kbd_keycode drivers/tty/vt/keyboard.c:1497 [inline]
kbd_event+0x2e8b/0x4270 drivers/tty/vt/keyboard.c:1515
input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2541
input_pass_values+0x288/0x890 drivers/input/input.c:128
input_event_dispose+0x3e5/0x6b0 drivers/input/input.c:353
input_event+0x89/0xe0 drivers/input/input.c:396
hidinput_hid_event+0x1487/0x1e60 drivers/hid/hid-input.c:1747
hid_process_event+0x4be/0x620 drivers/hid/hid-core.c:1565
hid_input_array_field+0x297/0x5f0 drivers/hid/hid-core.c:1669
hid_process_report drivers/hid/hid-core.c:1719 [inline]
hid_report_raw_event+0xdd7/0x1720 drivers/hid/hid-core.c:2074
__hid_input_report drivers/hid/hid-core.c:2144 [inline]
hid_input_report+0x44b/0x580 drivers/hid/hid-core.c:2166
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+0xbbd/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1785 [inline]
__hrtimer_run_queues+0x527/0xc30 kernel/time/hrtimer.c:1849
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1866
handle_softirqs+0x22a/0x7c0 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:727
irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:62
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1bd/0x500 kernel/sched/idle.c:332
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147
to a SOFTIRQ-irq-unsafe lock:
(tasklist_lock){.+.+}-{3:3}
... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock include/linux/rwlock_api_smp.h:161 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
__do_wait+0xde/0x740 kernel/exit.c:1672
do_wait+0x1e7/0x4f0 kernel/exit.c:1716
kernel_wait+0xd6/0x1c0 kernel/exit.c:1892
call_usermodehelper_exec_sync kernel/umh.c:136 [inline]
call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163
process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9af/0xee0 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 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:
&tty->flow.lock --> &f_owner->lock --> tasklist_lock
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(tasklist_lock);
local_irq_disable();
lock(&tty->flow.lock);
lock(&f_owner->lock);
<Interrupt>
lock(&tty->flow.lock);
*** DEADLOCK ***
2 locks held by syz.8.9383/1583:
#0: ffff88807cb08fa0 (&u->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:344 [inline]
#0: ffff88807cb08fa0 (&u->lock){+.+.}-{3:3}, at: queue_oob+0x1b6/0x4f0 net/unix/af_unix.c:2336
#1: ffff888029bd5720 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x55/0x420 fs/fcntl.c:962
the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&tty->flow.lock){..-.}-{3:3} {
IN-SOFTIRQ-W at:
lock_acquire+0x106/0x330 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:162
class_spinlock_irqsave_constructor include/linux/spinlock.h:617 [inline]
stop_tty+0x2f/0x150 drivers/tty/tty_io.c:765
kbd_keycode drivers/tty/vt/keyboard.c:1497 [inline]
kbd_event+0x2e8b/0x4270 drivers/tty/vt/keyboard.c:1515
input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2541
input_pass_values+0x288/0x890 drivers/input/input.c:128
input_event_dispose+0x3e5/0x6b0 drivers/input/input.c:353
input_event+0x89/0xe0 drivers/input/input.c:396
hidinput_hid_event+0x1487/0x1e60 drivers/hid/hid-input.c:1747
hid_process_event+0x4be/0x620 drivers/hid/hid-core.c:1565
hid_input_array_field+0x297/0x5f0 drivers/hid/hid-core.c:1669
hid_process_report drivers/hid/hid-core.c:1719 [inline]
hid_report_raw_event+0xdd7/0x1720 drivers/hid/hid-core.c:2074
__hid_input_report drivers/hid/hid-core.c:2144 [inline]
hid_input_report+0x44b/0x580 drivers/hid/hid-core.c:2166
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+0xbbd/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1785 [inline]
__hrtimer_run_queues+0x527/0xc30 kernel/time/hrtimer.c:1849
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1866
handle_softirqs+0x22a/0x7c0 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:727
irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:62
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1bd/0x500 kernel/sched/idle.c:332
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147
INITIAL USE at:
lock_acquire+0x106/0x330 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:162
class_spinlock_irqsave_constructor include/linux/spinlock.h:617 [inline]
start_tty+0x20/0x70 drivers/tty/tty_io.c:793
n_tty_set_termios+0xa7c/0x10c0 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+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
}
... key at: [<ffffffff9a296e80>] alloc_tty_struct.__key.35+0x0/0x20
-> (&new->fa_lock){....}-{3:3} {
INITIAL USE at:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_write_lock_irq include/linux/rwlock_api_smp.h:211 [inline]
_raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:326
fasync_remove_entry+0xf1/0x1c0 fs/fcntl.c:1012
lease_modify+0x1ca/0x3c0 fs/locks.c:1514
locks_remove_lease fs/locks.c:2757 [inline]
locks_remove_file+0x5f0/0xf70 fs/locks.c:2782
__fput+0x3ae/0xa70 fs/file_table.c:460
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:44 [inline]
exit_to_user_mode_loop+0xed/0x480 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+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
INITIAL READ USE at:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:172 [inline]
_raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:236
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+0x86f/0x1730 fs/locks.c:1657
break_deleg include/linux/filelock.h:504 [inline]
try_break_deleg include/linux/filelock.h:523 [inline]
lookup_open fs/namei.c:4472 [inline]
open_last_lookups fs/namei.c:4583 [inline]
path_openat+0x1eaa/0x3860 fs/namei.c:4827
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
}
... key at: [<ffffffff99fb8920>] fasync_insert_entry.__key+0x0/0x20
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:172 [inline]
_raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:236
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+0x2b/0x70 drivers/tty/tty_io.c:794
n_tty_set_termios+0xa7c/0x10c0 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+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> (&f_owner->lock){....}-{3:3} {
INITIAL USE at:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_write_lock_irq include/linux/rwlock_api_smp.h:211 [inline]
_raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:326
__f_setown+0x67/0x370 fs/fcntl.c:136
generic_add_lease fs/locks.c:1908 [inline]
generic_setlease+0xacf/0xf90 fs/locks.c:1984
do_fcntl_add_lease+0x35e/0x470 fs/locks.c:2086
fcntl_setdeleg+0x14c/0x1e0 fs/locks.c:2132
do_fcntl+0xdb6/0x1a50 fs/fcntl.c:564
__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+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
INITIAL READ USE at:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:172 [inline]
_raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:236
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+0x86f/0x1730 fs/locks.c:1657
break_deleg include/linux/filelock.h:504 [inline]
try_break_deleg include/linux/filelock.h:523 [inline]
lookup_open fs/namei.c:4472 [inline]
open_last_lookups fs/namei.c:4583 [inline]
path_openat+0x1eaa/0x3860 fs/namei.c:4827
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
}
... key at: [<ffffffff99fb8900>] file_f_owner_allocate.__key+0x0/0x20
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:172 [inline]
_raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:236
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+0x86f/0x1730 fs/locks.c:1657
break_deleg include/linux/filelock.h:504 [inline]
try_break_deleg include/linux/filelock.h:523 [inline]
lookup_open fs/namei.c:4472 [inline]
open_last_lookups fs/namei.c:4583 [inline]
path_openat+0x1eaa/0x3860 fs/namei.c:4827
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
the dependencies between the lock to be acquired
and SOFTIRQ-irq-unsafe lock:
-> (tasklist_lock){.+.+}-{3:3} {
HARDIRQ-ON-R at:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock include/linux/rwlock_api_smp.h:161 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
__do_wait+0xde/0x740 kernel/exit.c:1672
do_wait+0x1e7/0x4f0 kernel/exit.c:1716
kernel_wait+0xd6/0x1c0 kernel/exit.c:1892
call_usermodehelper_exec_sync kernel/umh.c:136 [inline]
call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163
process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9af/0xee0 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 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+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock include/linux/rwlock_api_smp.h:161 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
__do_wait+0xde/0x740 kernel/exit.c:1672
do_wait+0x1e7/0x4f0 kernel/exit.c:1716
kernel_wait+0xd6/0x1c0 kernel/exit.c:1892
call_usermodehelper_exec_sync kernel/umh.c:136 [inline]
call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163
process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9af/0xee0 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INITIAL USE at:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_write_lock_irq include/linux/rwlock_api_smp.h:211 [inline]
_raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:326
copy_process+0x23e6/0x3bd0 kernel/fork.c:2364
kernel_clone+0x248/0x870 kernel/fork.c:2648
user_mode_thread+0x110/0x180 kernel/fork.c:2724
rest_init+0x23/0x300 init/main.c:725
start_kernel+0x385/0x3d0 init/main.c:1210
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+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock include/linux/rwlock_api_smp.h:161 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
__do_wait+0xde/0x740 kernel/exit.c:1672
do_wait+0x1e7/0x4f0 kernel/exit.c:1716
kernel_wait+0xd6/0x1c0 kernel/exit.c:1892
call_usermodehelper_exec_sync kernel/umh.c:136 [inline]
call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163
process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0x9af/0xee0 kernel/workqueue.c:3443
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
}
... key at: [<ffffffff8e20c058>] tasklist_lock+0x18/0x40
... acquired at:
__raw_read_lock include/linux/rwlock_api_smp.h:161 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
send_sigurg+0x12b/0x420 fs/fcntl.c:978
sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3669
queue_oob+0x42c/0x4f0 net/unix/af_unix.c:2357
unix_stream_sendmsg+0xcb1/0xe80 net/unix/af_unix.c:2491
sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737
__sock_sendmsg net/socket.c:752 [inline]
____sys_sendmsg+0x589/0x8c0 net/socket.c:2610
___sys_sendmsg+0x2a5/0x360 net/socket.c:2664
__sys_sendmmsg+0x27c/0x4e0 net/socket.c:2753
__do_sys_sendmmsg net/socket.c:2780 [inline]
__se_sys_sendmmsg net/socket.c:2777 [inline]
__x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2777
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
stack backtrace:
CPU: 0 UID: 0 PID: 1583 Comm: syz.8.9383 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
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+0x106/0x330 kernel/locking/lockdep.c:5868
__raw_read_lock include/linux/rwlock_api_smp.h:161 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
send_sigurg+0x12b/0x420 fs/fcntl.c:978
sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3669
queue_oob+0x42c/0x4f0 net/unix/af_unix.c:2357
unix_stream_sendmsg+0xcb1/0xe80 net/unix/af_unix.c:2491
sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737
__sock_sendmsg net/socket.c:752 [inline]
____sys_sendmsg+0x589/0x8c0 net/socket.c:2610
___sys_sendmsg+0x2a5/0x360 net/socket.c:2664
__sys_sendmmsg+0x27c/0x4e0 net/socket.c:2753
__do_sys_sendmmsg net/socket.c:2780 [inline]
__se_sys_sendmmsg net/socket.c:2777 [inline]
__x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2777
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa19899acb9
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:00007fa19987f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fa198c15fa0 RCX: 00007fa19899acb9
RDX: 0000000000000001 RSI: 0000200000006c40 RDI: 0000000000000005
RBP: 00007fa198a08bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000040015 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa198c16038 R14: 00007fa198c15fa0 R15: 00007ffe0d856468
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026/01/20 19:15 | linux-next | d08c85ac8894 | 572effc1 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci-upstream-rust-kasan-gce | possible deadlock in stop_tty | ||
| 2025/12/11 03:55 | linux-next | 5ce74bc1b7cb | d6526ea3 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci-upstream-rust-kasan-gce | possible deadlock in stop_tty | ||
| 2025/10/31 03:52 | linux-next | 131f3d9446a6 | 2c50b6a9 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci-upstream-rust-kasan-gce | possible deadlock in stop_tty |