BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 50s! BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 37s! Showing busy workqueues and worker pools: workqueue events: flags=0x100 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=19 refcnt=20 in-flight: 1090:reg_todo for 50s pending: psi_avgs_work, 5*nsim_dev_hwstats_traffic_work, psi_avgs_work, vmstat_shepherd, drm_fb_helper_damage_work, 2*psi_avgs_work, 2*ovs_dp_masks_rebalance, delayed_vfree_work, psi_avgs_work, free_obj_work, xfrm_state_gc_task, rht_deferred_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=5 refcnt=6 pending: 4*ovs_dp_masks_rebalance, nsim_dev_hwstats_traffic_work workqueue events_unbound: flags=0x2 pwq 8: cpus=0-1 flags=0x6 nice=0 active=32 refcnt=33 in-flight: 1293:cfg80211_wiphy_work for 52s cfg80211_wiphy_work ,82:cfg80211_wiphy_work for 54s cfg80211_wiphy_work ,1415:cfg80211_wiphy_work for 46s cfg80211_wiphy_work ,13:cfg80211_wiphy_work for 54s cfg80211_wiphy_work ,1315:cfg80211_wiphy_work for 50s cfg80211_wiphy_work ,7746:cfg80211_wiphy_work for 33s ,1272:cfg80211_wiphy_work for 47s cfg80211_wiphy_work ,1458:cfg80211_wiphy_work for 52s cfg80211_wiphy_work ,1164:cfg80211_wiphy_work for 46s cfg80211_wiphy_work ,12:cfg80211_wiphy_work for 51s cfg80211_wiphy_work pending: 2*macvlan_process_broadcast, flush_memcg_stats_dwork, 5*macvlan_process_broadcast, cfg80211_wiphy_work, macvlan_process_broadcast, crng_reseed, 2*macvlan_process_broadcast pwq 8: cpus=0-1 flags=0x6 nice=0 active=7 refcnt=8 pending: 2*nsim_dev_trap_report_work, toggle_allocation_gate, 4*nsim_dev_trap_report_work workqueue events_power_efficient: flags=0x82 pwq 8: cpus=0-1 flags=0x6 nice=0 active=3 refcnt=4 in-flight: 41:gc_worker for 15s ,40:crda_timeout_work for 19s pending: do_cache_clean pwq 8: cpus=0-1 flags=0x6 nice=0 active=6 refcnt=7 pending: fb_flashcursor, neigh_managed_work, wg_ratelimiter_gc_entries, neigh_managed_work, 2*neigh_periodic_work workqueue events_dfl_long: flags=0x2 pwq 8: cpus=0-1 flags=0x6 nice=0 active=2 refcnt=3 pending: 2*defense_work_handler pwq 8: cpus=0-1 flags=0x6 nice=0 active=4 refcnt=5 pending: 4*defense_work_handler workqueue mm_percpu_wq: flags=0x108 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: vmstat_update workqueue kblockd: flags=0x118 pwq 3: cpus=0 node=0 flags=0x0 nice=-20 active=2 refcnt=3 pending: blk_mq_timeout_work, blk_mq_requeue_work workqueue bat_events: flags=0x6000a pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=44 MAYDAY in-flight: 2859(RESCUER):batadv_tt_purge for 3s pending: mayday_cursor_func inactive: batadv_iv_send_outstanding_bat_ogm_packet, batadv_tt_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_tt_purge, batadv_bla_periodic_work, batadv_dat_purge, 5*batadv_mcast_mla_update, 2*batadv_purge_orig, 3*batadv_iv_send_outstanding_bat_ogm_packet, 2*batadv_purge_orig, 5*batadv_iv_send_outstanding_bat_ogm_packet, batadv_purge_orig, 6*batadv_iv_send_outstanding_bat_ogm_packet, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_tt_purge workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_decrypt_worker, wg_packet_tx_worker, wg_packet_encrypt_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_tx_worker, wg_packet_decrypt_worker, wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_decrypt_worker, wg_packet_tx_worker, wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_decrypt_worker, wg_packet_encrypt_worker, wg_packet_tx_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker workqueue wg-kex-wg0: flags=0x6 pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker workqueue wg-kex-wg1: flags=0x6 pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_tx_worker, wg_packet_decrypt_worker, wg_packet_encrypt_worker pool 2: cpus=0 node=0 flags=0x0 nice=0 hung=50s workers=9 idle: 10 1013 9 4844 4829 4853 4815 4816 pool 8: cpus=0-1 flags=0x6 nice=0 hung=3s workers=13 manager: 7747 Showing backtraces of busy workers in stalled worker pools: pool 2: task:kworker/0:3 state:R running task stack:0 pid:1090 tgid:1090 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: events reg_todo Call trace: __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T) context_switch kernel/sched/core.c:5533 [inline] __schedule+0x135c/0x2b00 kernel/sched/core.c:7284 preempt_schedule_common+0xd4/0x190 kernel/sched/core.c:7463 preempt_schedule+0x60/0x78 kernel/sched/core.c:7487 __local_bh_enable_ip+0x16c/0x234 kernel/softirq.c:480 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:237 [inline] _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:245 spin_unlock_bh include/linux/spinlock.h:407 [inline] reg_process_pending_beacon_hints net/wireless/reg.c:3180 [inline] reg_todo+0x608/0x6a4 net/wireless/reg.c:3241 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0x91c/0x1250 kernel/workqueue.c:3479 worker_thread+0x798/0xbd0 kernel/workqueue.c:3560 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:854 pool 3: no worker in running state, cpu=0 is busy (nr_workers=2 nr_idle=2) The pool might have trouble waking an idle worker. Backtrace of last woken worker: task:kworker/0:1H state:R running task stack:0 pid:4387 tgid:4387 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: 0x0 (kblockd) Call trace: __switch_to+0x2b4/0x6e4 arch/arm64/kernel/process.c:775 (T) context_switch kernel/sched/core.c:5533 [inline] __schedule+0x135c/0x2b00 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x13c/0x20c kernel/sched/core.c:7376 worker_thread+0x924/0xbd0 kernel/workqueue.c:3575 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:854 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 2859 Comm: kworker/R-bat_e Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/23/2026 Workqueue: bat_events batadv_tt_purge Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 nmi_cpu_backtrace+0x270/0x2b8 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x1c0/0x430 lib/nmi_backtrace.c:66 arch_trigger_cpumask_backtrace+0x30/0x40 arch/arm64/kernel/smp.c:972 cpumask_backtrace+0x28/0x38 lib/nmi_backtrace.c:136 trigger_single_cpu_backtrace include/linux/nmi.h:182 [inline] show_cpu_pool_busy_workers kernel/workqueue.c:7885 [inline] show_cpu_pools_busy_workers+0x640/0x830 kernel/workqueue.c:7899 wq_watchdog_timer_fn+0x648/0x740 kernel/workqueue.c:8015 call_timer_fn+0x198/0x7f4 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x530/0x744 kernel/time/timer.c:2386 run_timer_base+0x84/0x1b8 kernel/time/timer.c:2395 run_timer_softirq+0x28/0x48 kernel/time/timer.c:2406 handle_softirqs+0x324/0xcbc kernel/softirq.c:645 __do_softirq+0x14/0x20 kernel/softirq.c:679 ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:78 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:901 do_softirq_own_stack+0x1c/0x28 arch/arm64/kernel/irq.c:83 do_softirq+0x90/0xf8 kernel/softirq.c:546 __local_bh_enable_ip+0x190/0x234 kernel/softirq.c:473 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:237 [inline] _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:245 spin_unlock_bh include/linux/spinlock.h:407 [inline] batadv_tt_local_purge+0x274/0x2f0 net/batman-adv/translation-table.c:1402 batadv_tt_purge+0x44/0x7b4 net/batman-adv/translation-table.c:3753 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0x91c/0x1250 kernel/workqueue.c:3479 rescuer_thread+0x68c/0xd90 kernel/workqueue.c:3703 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:854