BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 261s!
INFO: task kworker/u4:5:1856 blocked for more than 140 seconds.
Showing busy workqueues and worker pools:
      Not tainted 4.14.104+ #22
workqueue events: flags=0x0
  pwq 0:
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 cpus=0
kworker/u4:5    D
 node=0
25728  1856      2 0x80000000
 flags=0x0 nice=0
Workqueue: netns cleanup_net
 active=39/256
    in-flight: 3:rtc_timer_do_work
    pending: key_garbage_collector, vmstat_shepherd
, free_ioctx
Call Trace:
, destroy_super_work
, destroy_super_work, bpf_prog_free_deferred, proc_cleanup_work, proc_cleanup_work
, proc_cleanup_work, proc_cleanup_work, wait_rcu_exp_gp, free_ioctx, free_obj_work, proc_cleanup_work
, proc_cleanup_work, proc_cleanup_work, proc_cleanup_work, proc_cleanup_work, bpf_prog_free_deferred
, proc_cleanup_work, proc_cleanup_work, proc_cleanup_work, proc_cleanup_work, bpf_map_free_deferred, bpf_map_free_deferred
, proc_cleanup_work, proc_cleanup_work, proc_cleanup_work, destroy_super_work, proc_cleanup_work
, proc_cleanup_work, proc_cleanup_work, destroy_super_work, binder_deferred_func, proc_cleanup_work, proc_cleanup_work
 schedule+0x92/0x1c0 kernel/sched/core.c:3492
, proc_cleanup_work, proc_cleanup_work

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