INFO: task kworker/1:4:5896 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:21024 pid:5896 tgid:5896 ppid:2 task_flags:0x4208160 flags:0x00080000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 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+0x7fe/0x1300 kernel/locking/mutex.c:776 class_wiphy_constructor include/net/cfg80211.h:6360 [inline] reg_leave_invalid_chans net/wireless/reg.c:2441 [inline] reg_check_chans_work+0x15a/0xf40 net/wireless/reg.c:2456 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 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: 1 lock held by kthreadd/2: 1 lock held by kworker/R-kvfre/6: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 3 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: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2672 3 locks held by kworker/1:0/24: #0: ffff88813fe51948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813fe51948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc900001e7bc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900001e7bc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8f9ac148 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 1 lock held by khungtaskd/32: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/37: 7 locks held by kworker/u8:3/50: 3 locks held by kworker/u8:4/78: 2 locks held by kworker/0:2/791: 3 locks held by kworker/1:2/2145: 1 lock held by kworker/R-bat_e/3400: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 3 locks held by kworker/u8:5/3412: 3 locks held by kworker/u8:6/3426: 2 locks held by klogd/5176: 2 locks held by udevd/5187: 3 locks held by crond/5560: 2 locks held by getty/5572: #0: ffff8880345c00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5804: 2 locks held by syz-executor/5824: 2 locks held by syz-executor/5826: 5 locks held by syz-executor/5841: 1 lock held by kworker/R-wg-cr/5862: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5867: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5872: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5875: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5880: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5881: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/5882: 2 locks held by kworker/1:3/5895: 4 locks held by kworker/1:4/5896: #0: ffff88813fe52948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813fe52948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90004befbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90004befbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8f9ac148 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa5/0xf40 net/wireless/reg.c:2453 #3: ffff888035100788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6360 [inline] #3: ffff888035100788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2441 [inline] #3: ffff888035100788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x15a/0xf40 net/wireless/reg.c:2456 3 locks held by kworker/1:5/5903: 3 locks held by kworker/1:6/5922: 3 locks held by kworker/u8:7/5941: 1 lock held by kworker/0:7/5994: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2672 4 locks held by udevd/6066: 2 locks held by syz-executor/15245: 1 lock held by kworker/R-wg-cr/15376: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/15380: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/15381: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by kworker/R-wg-cr/15596: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2730 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x593/0x1390 kernel/workqueue.c:3560 1 lock held by syz-executor/15736: 3 locks held by kworker/u8:8/15747: 3 locks held by kworker/u8:9/15868: 1 lock held by kworker/R-wg-cr/15906: 6 locks held by syz.7.5056/17859: 3 locks held by kworker/u8:10/17873: 4 locks held by kworker/u8:11/17874: #0: ffff888034634948 ((wq_completion)wg-kex-wg1#7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888034634948 ((wq_completion)wg-kex-wg1#7){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000b297bc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000b297bc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff8880326e1308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x12f/0x830 drivers/net/wireguard/noise.c:529 #3: ffff888056e9b4c0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x140/0x830 drivers/net/wireguard/noise.c:530 4 locks held by kworker/u8:12/17877: 3 locks held by kworker/u8:13/17878: 3 locks held by kworker/u8:14/17879: 3 locks held by kworker/u8:15/17880: #0: ffff88814c367948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88814c367948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90004aafbc0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90004aafbc0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8f9ac148 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f9ac148 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 1 lock held by syz-executor/17881: 4 locks held by kworker/u8:16/17882: 2 locks held by dhcpcd-run-hook/17883: 2 locks held by kworker/1:1/17885: 1 lock held by kworker/u9:1/17886: #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: set_pf_worker kernel/workqueue.c:3346 [inline] #0: ffffffff8e3f8c88 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_thread+0x5c/0x1360 kernel/workqueue.c:3372 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 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: 50 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:__lock_acquire+0x74/0x2cf0 kernel/locking/lockdep.c:5103 Code: b6 93 0f 84 da 13 00 00 41 89 cd 41 89 d6 8b 0d 22 33 a2 0c 85 c9 44 0f 44 c1 31 c9 48 3d b0 83 b6 93 41 0f 45 c8 89 4c 24 10 <8b> 0d 06 c3 5d 18 85 c9 0f 95 c0 83 fe 08 0f 92 c2 08 c2 0f 84 49 RSP: 0018:ffffc90000a07bf0 EFLAGS: 00000006 RAX: ffffffff9a023be0 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e55a360 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8e55a360 R10: dffffc0000000000 R11: ffffffff81afb170 R12: 0000000000000002 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881257f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc6a9be5c98 CR3: 0000000077d01000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x370/0x6e0 mm/slub.c:5270 skb_clone+0x212/0x3a0 net/core/skbuff.c:2088 deliver_clone net/bridge/br_forward.c:125 [inline] maybe_deliver net/bridge/br_forward.c:191 [inline] br_flood+0x6cb/0xb80 net/bridge/br_forward.c:238 br_handle_frame_finish+0x1492/0x1b40 net/bridge/br_input.c:229 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0xa3a/0xd70 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x374/0x6f0 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x1277/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x98f/0x30a0 net/core/dev.c:6039 __netif_receive_skb_one_core net/core/dev.c:6150 [inline] __netif_receive_skb net/core/dev.c:6265 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6617 __napi_poll+0xae/0x340 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7896 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 ieee80211_rx_bss_info net/mac80211/ibss.c:1166 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline] ieee80211_ibss_rx_queued_mgmt+0x1ac7/0x2c80 net/mac80211/ibss.c:1602 ieee80211_iface_process_skb net/mac80211/iface.c:1740 [inline] ieee80211_iface_work+0x85e/0x12b0 net/mac80211/iface.c:1794 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246