INFO: task syz.4.5139:24081 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.5139 state:D stack:25400 pid:24081 tgid:24081 ppid:17653 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
pipe_release+0x48/0x330 fs/pipe.c:729
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 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+0xef/0x4e0 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
RIP: 0033:0x7f775af8f749
RSP: 002b:00007ffdcd2c78b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f775b1e7da0 RCX: 00007f775af8f749
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f775b1e7da0 R08: 000000000000016c R09: 00000015cd2c7baf
R10: 00007f775b1e7cb0 R11: 0000000000000246 R12: 00000000000b84c7
R13: 00007f775b1e6090 R14: ffffffffffffffff R15: 00007ffdcd2c79d0
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by udevd/5202:
2 locks held by getty/5591:
#0: ffff8880343df0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/16547:
1 lock held by syz-executor/16877:
1 lock held by udevd/22699:
1 lock held by syz.4.5139/24081:
#0: ffff888020bab068 (&pipe->mutex){+.+.}-{4:4}, at: pipe_release+0x48/0x330 fs/pipe.c:729
1 lock held by syz.4.5139/24082:
#0: ffff888020bab068 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x2e/0x440 fs/splice.c:1289
1 lock held by syz.2.5154/24125:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5818 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:find_held_lock kernel/locking/lockdep.c:5348 [inline]
RIP: 0010:__lock_release kernel/locking/lockdep.c:5535 [inline]
RIP: 0010:lock_release+0xf2/0x3b0 kernel/locking/lockdep.c:5889
Code: 84 17 01 00 00 4c 89 6c 24 18 48 89 5c 24 08 44 8d 60 ff 49 8d af 30 0b 00 00 4d 63 ec 48 89 04 24 83 f8 32 0f 83 2a 02 00 00 <4a> 8d 1c ad 00 00 00 00 4c 01 eb 48 8d 6c dd 00 48 89 ef 4c 89 f6
RSP: 0018:ffffc90003fffcb8 EFLAGS: 00000097
RAX: 0000000000000001 RBX: 0000000000000083 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8d7a6998 RDI: ffffffff8bc083e0
RBP: ffff88807d2a8b30 R08: ffff88807d2a8007 R09: 1ffff1100fa55000
R10: dffffc0000000000 R11: ffffed100fa55001 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88802bb10018 R15: ffff88807d2a8000
FS: 00005555768f8500(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffff32e4e40 CR3: 00000000324ba000 CR4: 00000000003526f0
Call Trace:
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:157 [inline]
_raw_spin_unlock_irq+0x16/0x50 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:401 [inline]
__set_current_blocked kernel/signal.c:3222 [inline]
set_current_blocked kernel/signal.c:3206 [inline]
signal_delivered kernel/signal.c:3070 [inline]
signal_setup_done+0x227/0x3b0 kernel/signal.c:3082
handle_signal arch/x86/kernel/signal.c:312 [inline]
arch_do_signal_or_restart+0x465/0x7a0 arch/x86/kernel/signal.c:339
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4e0 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
RIP: 0033:0x7fb1ae64d6f0
Code: 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 fb 44 8d 56
RSP: 002b:00007ffe8e13ff78 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 00007ffe8e140a90 RCX: 00007fb1ae78f50c
RDX: 00007ffe8e13ff80 RSI: 00007ffe8e1400b0 RDI: 0000000000000011
RBP: 00007ffe8e140640 R08: 00007ffe8e140540 R09: 00007ffe8e140550
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffe8e1408e0
R13: 0000000000000000 R14: 00007ffe8e140960 R15: 585858582e7a7973