BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 55s! Showing busy workqueues and worker pools: workqueue events: flags=0x100 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=13 refcnt=14 in-flight: 10:reg_todo for 55s pending: 2*nsim_dev_hwstats_traffic_work, psi_avgs_work, vmstat_shepherd, 2*ovs_dp_masks_rebalance, psi_avgs_work, free_obj_work, delayed_vfree_work, 3*psi_avgs_work pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: psi_avgs_work workqueue events_unbound: flags=0x2 pwq 8: cpus=0-1 flags=0x6 nice=0 active=6 refcnt=8 in-flight: 5233:fsnotify_mark_destroy_workfn for 55s BAR(5627) ,40:fsnotify_connector_destroy_workfn for 55s ,93:cfg80211_wiphy_work for 64s cfg80211_wiphy_work ,12:cfg80211_wiphy_work for 63s cfg80211_wiphy_work pwq 8: cpus=0-1 flags=0x6 nice=0 active=26 refcnt=27 in-flight: 5649:nsim_dev_trap_report_work for 4s ,3651:cfg80211_wiphy_work for 66s cfg80211_wiphy_work ,1242:nsim_dev_trap_report_work for 1s ,14:cfg80211_wiphy_work for 38s cfg80211_wiphy_work ,1108:cfg80211_wiphy_work for 64s cfg80211_wiphy_work ,42:cfg80211_wiphy_work for 66s cfg80211_wiphy_work pending: macvlan_process_broadcast, flush_memcg_stats_dwork, cfg80211_wiphy_work, nsim_dev_trap_report_work, crng_reseed, toggle_allocation_gate, nsim_dev_trap_report_work, fsnotify_connector_destroy_workfn, fsnotify_mark_destroy_workfn, 6*cfg80211_wiphy_work, nsim_dev_trap_report_work workqueue events_power_efficient: flags=0x82 pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2 pending: crda_timeout_work pwq 8: cpus=0-1 flags=0x6 nice=0 active=7 refcnt=8 in-flight: 3486:neigh_periodic_work for 41s pending: fb_flashcursor, gc_worker, neigh_managed_work, do_cache_clean, wg_ratelimiter_gc_entries, neigh_periodic_work workqueue events_dfl_long: flags=0x2 pwq 8: cpus=0-1 flags=0x6 nice=0 active=6 refcnt=7 pending: 6*defense_work_handler workqueue rcu_gp: flags=0x108 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: process_srcu workqueue mm_percpu_wq: flags=0x108 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: vmstat_update workqueue bat_events: flags=0x6000a pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=36 MAYDAY in-flight: 2855(RESCUER):batadv_tt_purge for 15s pending: mayday_cursor_func inactive: 2*batadv_tt_purge, batadv_purge_orig, 5*batadv_mcast_mla_update, 6*batadv_iv_send_outstanding_bat_ogm_packet, 4*batadv_purge_orig, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, 2*batadv_tt_purge 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 pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 in-flight: 4813:wg_packet_encrypt_worker for 0s workqueue wg-crypt-wg1: 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-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x6 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_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 in-flight: 5648:wg_packet_handshake_send_worker for 3s workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x6 nice=0 active=2 refcnt=3 pending: 2*wg_packet_handshake_send_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 pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_tx_worker workqueue wg-kex-wg1: flags=0x124 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_receive_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_tx_worker, wg_packet_encrypt_worker, wg_packet_decrypt_worker workqueue wg-kex-wg2: flags=0x124 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_receive_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 pool 2: cpus=0 node=0 flags=0x0 nice=0 hung=55s workers=8 idle: 1241 865 4803 5100 9 4795 4802 pool 6: cpus=1 node=0 flags=0x0 nice=0 hung=0s workers=7 idle: 1011 24 4810 4887 4816 26 pool 8: cpus=0-1 flags=0x6 nice=0 hung=1s workers=13 manager: 5650 Showing backtraces of busy workers in stalled worker pools: pool 2: no worker in running state, cpu=0 is busy (nr_workers=8 nr_idle=7) The pool might have trouble waking an idle worker. Backtrace of last woken worker: task:kworker/0:3 state:R running task stack:0 pid:1241 tgid:1241 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: 0x0 (events) 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: 2855 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026 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+0x14/0x20 arch/arm64/kernel/irq.c:78 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:901 do_softirq_own_stack+0x20/0x2c 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_global_purge net/batman-adv/translation-table.c:2390 [inline] batadv_tt_purge+0x3e4/0x7b4 net/batman-adv/translation-table.c:3754 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