BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 33s!
Showing busy workqueues and worker pools:
workqueue events: flags=0x0
  pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=4/256
    pending: defense_work_handler, defense_work_handler, defense_work_handler, key_garbage_collector
workqueue events_power_efficient: flags=0x80
workqueue kblockd: flags=0x18
  pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=1/256
    pending: blk_mq_requeue_work
workqueue dm_bufio_cache: flags=0x8
  pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
    pending: work_fn