BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 31s! BUG: workqueue lockup - pool cpus=0-1 flags=0x4 nice=0 stuck for 30s! Showing busy workqueues and worker pools: workqueue events: flags=0x0 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=5/256 pending: defense_work_handler, defense_work_handler, defense_work_handler, vmstat_shepherd, cache_reap workqueue events_power_efficient: flags=0x80 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=2/256 pending: gc_worker, do_cache_clean workqueue mm_percpu_wq: flags=0x8 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 pending: vmstat_update workqueue writeback: flags=0x4e pwq 4: cpus=0-1 flags=0x4 nice=0 active=9/256 pending: wb_workfn, wb_workfn, wb_workfn, wb_workfn, wb_workfn, wb_workfn, wb_workfn, wb_workfn, wb_workfn workqueue dm_bufio_cache: flags=0x8 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 pending: work_fn workqueue ipv6_addrconf: flags=0x40008 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1 pending: addrconf_verify_work