INFO: task kworker/u8:4:61 blocked for more than 143 seconds.
      Not tainted 6.9.0-syzkaller-12088-g52a2f0608366 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:19640 pid:61    tgid:61    ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3871
 nsim_fib_create+0x8a6/0xa70 drivers/net/netdevsim/fib.c:1587