INFO: task kworker/0:2:115 blocked for more than 157 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:20584 pid:115 tgid:115 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events reg_todo Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 class_wiphy_constructor include/net/cfg80211.h:6358 [inline] reg_process_self_managed_hints+0xaf/0x1c0 net/wireless/reg.c:3179 reg_todo+0x78d/0x890 net/wireless/reg.c:3192 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by kthreadd/2: 3 locks held by kworker/0:0/9: #0: ffff88801b01a948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801b01a948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc900000e7ba0 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900000e7ba0 ((crda_timeout).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f9538c8 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x15/0x50 net/wireless/reg.c:541 6 locks held by kworker/0:1/10: 3 locks held by kworker/u8:0/12: 3 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 5 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e53d320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e53d320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by kworker/R-write/33: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2678 3 locks held by kworker/u8:2/36: 3 locks held by kworker/1:1/43: 3 locks held by kworker/u8:3/50: 3 locks held by kworker/u8:4/60: 4 locks held by kworker/0:2/115: #0: ffff88801b019948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801b019948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90002d97ba0 (reg_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90002d97ba0 (reg_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f9538c8 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0x890 net/wireless/reg.c:3189 #3: ffff888065b60788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6358 [inline] #3: ffff888065b60788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_process_self_managed_hints+0xaf/0x1c0 net/wireless/reg.c:3179 3 locks held by kworker/u8:5/774: 3 locks held by kworker/1:2/939: 4 locks held by kworker/u8:6/1096: 3 locks held by kworker/u8:7/1113: 3 locks held by kworker/u8:8/1163: 1 lock held by kworker/R-krdsd/3416: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2678 1 lock held by klogd/5223: 3 locks held by udevd/5234: 2 locks held by dhcpcd/5528: 5 locks held by dhcpcd/5529: 1 lock held by crond/5606: 2 locks held by getty/5624: #0: ffff8880317530a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5849: 3 locks held by kworker/0:3/5860: 1 lock held by syz-executor/5868: 3 locks held by kworker/0:4/5875: 1 lock held by kworker/R-wg-cr/5887: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5888: 1 lock held by kworker/R-wg-cr/5890: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5892: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5893: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5894: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5895: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5896: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5897: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5898: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5899: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/R-wg-cr/5900: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x88b/0xdd0 kernel/workqueue.c:3556 1 lock held by kworker/1:3/5901: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2678 3 locks held by kworker/1:4/5908: 4 locks held by kworker/0:5/5927: 3 locks held by kworker/0:6/5944: 4 locks held by kworker/1:5/5950: #0: ffff88814c71c948 ((wq_completion)wg-kex-wg1#6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88814c71c948 ((wq_completion)wg-kex-wg1#6){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90005427ba0 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90005427ba0 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888034ea1348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x150/0x900 drivers/net/wireguard/noise.c:598 #3: ffff88806735b4c0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x4bf/0x900 drivers/net/wireguard/noise.c:632 3 locks held by kworker/1:6/5985: 4 locks held by kworker/1:7/5986: #0: ffff88802a1e6948 ((wq_completion)wg-kex-wg2#6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88802a1e6948 ((wq_completion)wg-kex-wg2#6){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90005577ba0 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90005577ba0 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __ptr = (unsigned long) ((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker)))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888034ea5348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x150/0x900 drivers/net/wireguard/noise.c:598 #3: ffff888066f6aad8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x4bf/0x900 drivers/net/wireguard/noise.c:632 1 lock held by syz.0.87/6318: 6 locks held by syz.1.123/6426: 4 locks held by kworker/u8:9/6436: 4 locks held by kworker/u8:10/6437: 4 locks held by syz.0.125/6439: 4 locks held by kworker/u8:11/6441: 1 lock held by syz.2.126/6443: #0: ffffffff8f9538c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f9538c8 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x83c/0x1150 net/core/dev_ioctl.c:864 4 locks held by kworker/u8:12/6445: 4 locks held by kworker/u8:13/6446: 3 locks held by kworker/u8:14/6447: #0: ffff88803106b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88803106b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000bd9fba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000bd9fba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f9538c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f9538c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 4 locks held by kworker/u8:15/6448: 4 locks held by kworker/u8:16/6450: 3 locks held by kworker/u8:17/6452: 4 locks held by syz-executor/6453: 1 lock held by kworker/0:7/6455: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: set_pf_worker kernel/workqueue.c:3352 [inline] #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_thread+0x5c/0xda0 kernel/workqueue.c:3378 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6441 Comm: kworker/u8:11 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: bat_events batadv_tt_purge RIP: 0010:check_preemption_disabled+0xa/0x120 lib/smp_processor_id.c:13 Code: 05 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 <65> 48 8b 05 de 14 5e 07 48 89 44 24 08 65 8b 05 e6 14 5e 07 65 8b RSP: 0018:ffffc900000072f8 EFLAGS: 00000282 RAX: 0000000000000000 RBX: ffffffff9079fe01 RCX: 56864ef10a894000 RDX: ffffc90000007401 RSI: ffffffff8c056e40 RDI: ffffffff8c056e00 RBP: dffffc0000000000 R08: ffffc900000075c0 R09: 0000000000000000 R10: ffffc900000074d8 R11: fffff52000000e9d R12: ffffc900000075d0 R13: ffffffff81746d25 R14: ffffffff8e53d320 R15: ffffffff81746d25 FS: 0000000000000000(0000) GS:ffff8881257b7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ff08623660 CR3: 0000000066464000 CR4: 00000000003526f0 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2507 [inline] slab_free mm/slub.c:6557 [inline] kmem_cache_free+0x19b/0x690 mm/slub.c:6668 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ip6_mc_input+0x8de/0xb70 net/ipv6/ip6_input.c:593 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6078 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6191 process_backlog+0x60e/0x14f0 net/core/dev.c:6543 __napi_poll+0xc7/0x360 net/core/dev.c:7593 napi_poll net/core/dev.c:7656 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7783 handle_softirqs+0x286/0x870 kernel/softirq.c:622 do_softirq+0xec/0x180 kernel/softirq.c:523 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_global_purge net/batman-adv/translation-table.c:2250 [inline] batadv_tt_purge+0x4d1/0x9e0 net/batman-adv/translation-table.c:3510 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245