INFO: task kworker/0:2:1210 blocked for more than 154 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:25912 pid:1210 tgid:1210 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events reg_todo Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 class_wiphy_constructor include/net/cfg80211.h:6360 [inline] reg_process_self_managed_hints+0x9e/0x1b0 net/wireless/reg.c:3179 reg_todo+0x5cf/0x800 net/wireless/reg.c:3192 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 2 locks held by kthreadd/2: 1 lock held by kworker/R-kvfre/6: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 3 locks held by kworker/0:0/9: 2 locks held by kworker/0:1/10: 3 locks held by kworker/u8:0/12: 4 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 3 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e5e3120 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/36: 4 locks held by kworker/1:1/43: 3 locks held by kworker/u8:3/50: 7 locks held by kworker/u8:4/65: 3 locks held by kworker/1:2/797: 3 locks held by kworker/u8:5/1149: 4 locks held by kworker/0:2/1210: #0: ffff88813fe15948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc9000400fc98 (reg_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0x800 net/wireless/reg.c:3189 #3: ffff8880227c8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6360 [inline] #3: ffff8880227c8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_process_self_managed_hints+0x9e/0x1b0 net/wireless/reg.c:3179 4 locks held by kworker/u8:6/1340: #0: ffff88801c29f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc9000439fc98 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903dcef0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xab/0x830 net/core/net_namespace.c:670 #3: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: cfg80211_pernet_exit+0x17/0x120 net/wireless/core.c:1693 3 locks held by kworker/R-ipv6_/3183: #0: ffff888030772948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc9000bbb7c20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734 1 lock held by kworker/R-krdsd/3396: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 4 locks held by kworker/R-bat_e/3408: 3 locks held by kworker/u8:7/4145: 2 locks held by klogd/5183: 2 locks held by udevd/5194: 4 locks held by dhcpcd/5489: 2 locks held by getty/5582: #0: ffff88814ee950a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5811: 3 locks held by syz-executor/5822: 2 locks held by syz-executor/5824: 1 lock held by syz-executor/5825: 1 lock held by kworker/0:3/5828: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672 1 lock held by kworker/R-wg-cr/5852: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5853: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5854: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5855: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5856: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5857: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5858: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5859: 1 lock held by kworker/R-wg-cr/5860: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5861: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2672 1 lock held by kworker/R-wg-cr/5862: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5863: #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e490a88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x6bb/0xf40 kernel/workqueue.c:3560 3 locks held by kworker/0:4/5864: #0: ffff88813fe16948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90004c6fc98 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x16/0x70 net/wireless/reg.c:541 5 locks held by kworker/1:3/5879: 3 locks held by kworker/0:5/5893: #0: ffff88813fe16948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90004e0fc98 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903f5828 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x10e0 net/wireless/reg.c:2453 4 locks held by kworker/0:6/5914: 3 locks held by kworker/1:5/5961: 3 locks held by syz.1.65/6311: 3 locks held by kworker/u8:8/6378: 4 locks held by kworker/u8:9/6379: 4 locks held by kworker/u8:10/6381: 3 locks held by kworker/u8:11/6382: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 3408 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: bat_events batadv_dat_purge RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x20 kernel/kcov.c:314 Code: bf 03 00 00 00 e9 58 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <89> f2 89 fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 0f 1f 84 00 00 00 RSP: 0018:ffffc90000a08778 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888032158000 RCX: ffffffff8a227186 RDX: ffff888030fd0000 RSI: 0000000000000080 RDI: 0000000000000000 RBP: ffff88807d5588c0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 1ffff920001410f4 R14: 0000000000000080 R15: ffffc90000a08800 FS: 0000000000000000(0000) GS:ffff8881246e3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000002004000 CR3: 000000000e392000 CR4: 00000000003526f0 Call Trace: ip6_pol_route+0x256/0x1230 net/ipv6/route.c:2323 pol_lookup_func include/net/ip6_fib.h:617 [inline] fib6_rule_lookup+0x52f/0x720 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2349 [inline] ip6_route_input+0x662/0xc50 net/ipv6/route.c:2652 ip6_rcv_finish_core.isra.0+0x1a9/0x5a0 net/ipv6/ip6_input.c:66 ip6_rcv_finish net/ipv6/ip6_input.c:77 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x1e8/0x610 net/ipv6/ip6_input.c:311 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6152 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6265 process_backlog+0x37a/0x1580 net/core/dev.c:6617 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0xa40/0xf20 net/core/dev.c:7896 handle_softirqs+0x1ea/0x910 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xac/0xe0 kernel/softirq.c:510 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] __batadv_dat_purge.part.0+0x294/0x3c0 net/batman-adv/distributed-arp-table.c:185 __batadv_dat_purge net/batman-adv/distributed-arp-table.c:166 [inline] batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:204 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] rescuer_thread+0x8f1/0xf40 kernel/workqueue.c:3528 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246