INFO: task kworker/0:7:4313 blocked for more than 143 seconds.
      Tainted: G S                syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:7     state:D stack:25664 pid: 4313 ppid:     2 flags:0x00004000
Workqueue: events console_callback
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
 __down_common+0x289/0x3b0 kernel/locking/semaphore.c:228
 down+0x7e/0xd0 kernel/locking/semaphore.c:63
 console_lock+0x29/0x70 kernel/printk/printk.c:2557
 console_callback+0x66/0x440 drivers/tty/vt/vt.c:2980
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/0:2/1324:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90004e07d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffff888025e30240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x283/0x3380 drivers/net/netdevsim/fib.c:1480
2 locks held by getty/3941:
 #0: ffff88802cd72098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:5/4253:
2 locks held by kworker/0:7/4313:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc9000331fd00 (console_work){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/0:8/4957:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90003e5fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffff88802f6df240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x283/0x3380 drivers/net/netdevsim/fib.c:1480
3 locks held by syz.3.360/5808:
1 lock held by syz.5.404/6078:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2064 [inline]
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x20a/0xcd0 drivers/tty/tty_io.c:2148
1 lock held by syz.6.460/6348:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: ptmx_open+0xd2/0x2c0 drivers/tty/pty.c:823
1 lock held by syz.2.524/6708:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: ptmx_open+0xd2/0x2c0 drivers/tty/pty.c:823
1 lock held by syz.8.570/6956:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: ptmx_open+0xd2/0x2c0 drivers/tty/pty.c:823
1 lock held by syz.0.581/7076:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2064 [inline]
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x20a/0xcd0 drivers/tty/tty_io.c:2148
1 lock held by syz.9.612/7228:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: ptmx_open+0xd2/0x2c0 drivers/tty/pty.c:823
1 lock held by syz.3.621/7312:
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2064 [inline]
 #0: ffffffff8c9f62e8 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x20a/0xcd0 drivers/tty/tty_io.c:2148
1 lock held by syz.3.621/7316:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Tainted: G S                syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe1b/0xe60 kernel/hung_task.c:369
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>