INFO: task kworker/0:7:5969 blocked for more than 154 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:7 state:D stack:15864 pid:5969 tgid:5969 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7118 __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_leave_invalid_chans net/wireless/reg.c:2441 [inline] reg_check_chans_work+0x170/0xf40 net/wireless/reg.c:2456 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 INFO: task kworker/u8:9:13020 blocked for more than 154 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:9 state:D stack:26344 pid:13020 tgid:13020 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7118 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 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: 2 locks held by kthreadd/2: 1 lock held by kworker/R-kvfre/6: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2678 4 locks held by kworker/0:0/9: 3 locks held by kworker/0:1/10: 3 locks held by kworker/u8:0/12: #0: ffff8880273c0148 ((wq_completion)wg-kex-wg2#13){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8880273c0148 ((wq_completion)wg-kex-wg2#13){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90000117ba0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90000117ba0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff88807a36c090 (&cookie->lock){++++}-{4:4}, at: wg_cookie_add_mac_to_packet+0x3e/0x1a0 drivers/net/wireguard/cookie.c:162 3 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: 1 lock held by khungtaskd/31: #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/36: 2 locks held by kworker/1:1/48: 2 locks held by kswapd0/87: 3 locks held by kworker/1:2/89: #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: ffffc900025cfba0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900025cfba0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f9523c8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u8:5/1100: 3 locks held by kworker/u8:6/1109: 4 locks held by kworker/0:2/3096: 6 locks held by kworker/R-bat_e/3426: 4 locks held by kworker/u8:10/3575: 1 lock held by klogd/5225: 1 lock held by udevd/5236: 2 locks held by crond/5609: 2 locks held by getty/5627: #0: ffff88814ddc00a0 (&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/5866: 3 locks held by kworker/1:3/5867: #0: ffff888030882d48 ((wq_completion)wg-kex-wg2#4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888030882d48 ((wq_completion)wg-kex-wg2#4){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000405fba0 ((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: ffffc9000405fba0 ((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: ffff888073352ad8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_begin_session+0x36/0xbd0 drivers/net/wireguard/noise.c:822 1 lock held by kworker/u9:3/5869: #0: ffffffff8e3e3c48 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2678 4 locks held by kworker/1:5/5918: 3 locks held by kworker/1:6/5919: 3 locks held by kworker/0:3/5950: 3 locks held by kworker/0:4/5952: 4 locks held by kworker/0:7/5969: #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: ffffc900045dfba0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900045dfba0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f9523c8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa1/0xf40 net/wireless/reg.c:2453 #3: ffff888071e20788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6358 [inline] #3: ffff888071e20788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2441 [inline] #3: ffff888071e20788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x170/0xf40 net/wireless/reg.c:2456 2 locks held by syz-executor/10152: 4 locks held by kworker/u8:3/12073: 4 locks held by syz-executor/12623: 4 locks held by kworker/0:6/12780: 4 locks held by dhcpcd-run-hook/12985: 4 locks held by syz.4.2096/13006: 3 locks held by kworker/u8:4/13016: 3 locks held by kworker/u8:7/13018: 4 locks held by kworker/u8:8/13019: 3 locks held by kworker/u8:9/13020: #0: ffff8880303a2148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8880303a2148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000bf57ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000bf57ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f9523c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f9523c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 4 locks held by kworker/u8:11/13022: #0: ffff8880273c5948 ((wq_completion)wg-kex-wg0#13){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8880273c5948 ((wq_completion)wg-kex-wg0#13){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000c08fba0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000c08fba0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff88807ab79348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x105/0x750 drivers/net/wireguard/noise.c:529 #3: ffff88805a299708 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x116/0x750 drivers/net/wireguard/noise.c:530 4 locks held by kworker/u8:12/13024: 4 locks held by kworker/u8:13/13025: 3 locks held by kworker/u8:14/13026: 2 locks held by syz-executor/13028: ============================================= 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: 3426 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: bat_events batadv_dat_purge RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:448 [inline] RIP: 0010:find_match+0x139/0xc90 net/ipv6/route.c:780 Code: 00 00 00 fc ff df 48 85 db 0f 84 12 0a 00 00 48 81 c3 58 06 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 3f 0a 00 00 <8b> 1b 31 ff 89 de e8 8c cb 7a f7 85 db 74 45 e8 43 c7 7a f7 43 0f RSP: 0018:ffffc900000066a0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888032acd658 RCX: ffff888030e31e40 RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 1ffff1100b2a5a19 R08: ffffc900000069a0 R09: ffffc900000069b0 R10: ffffc90000006800 R11: fffff52000000d02 R12: dffffc0000000000 R13: 0000000000000003 R14: 1ffff1100b2a5a1b R15: ffff88805952d0df FS: 0000000000000000(0000) GS:ffff8881257be000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee75334ff8 CR3: 000000000e338000 CR4: 00000000003526f0 Call Trace: __find_rr_leaf+0x23a/0x6d0 net/ipv6/route.c:868 find_rr_leaf net/ipv6/route.c:889 [inline] rt6_select net/ipv6/route.c:933 [inline] fib6_table_lookup+0x39f/0xa80 net/ipv6/route.c:2233 ip6_pol_route+0x222/0x1180 net/ipv6/route.c:2269 pol_lookup_func include/net/ip6_fib.h:617 [inline] fib6_rule_lookup+0x52f/0x6f0 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2338 [inline] ip6_route_input+0x6de/0xad0 net/ipv6/route.c:2641 ip6_rcv_finish+0x141/0x2e0 net/ipv6/ip6_input.c:77 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:990 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:6072 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6185 netif_receive_skb_internal net/core/dev.c:6271 [inline] netif_receive_skb+0x1cb/0x790 net/core/dev.c:6330 NF_HOOK+0xa0/0x390 include/linux/netfilter.h:319 br_handle_frame_finish+0x15c6/0x1c50 net/bridge/br_input.c:235 br_nf_hook_thresh+0x3c6/0x4a0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 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+0x982/0x14c0 net/bridge/br_input.c:442 __netif_receive_skb_core+0x10b9/0x4020 net/core/dev.c:5959 __netif_receive_skb_one_core net/core/dev.c:6070 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6185 process_backlog+0x60e/0x14f0 net/core/dev.c:6537 __napi_poll+0xc7/0x360 net/core/dev.c:7587 napi_poll net/core/dev.c:7650 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7777 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_dat_purge net/batman-adv/distributed-arp-table.c:185 [inline] batadv_dat_purge+0x2da/0x3c0 net/batman-adv/distributed-arp-table.c:204 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 rescuer_thread+0x53c/0xdd0 kernel/workqueue.c:3523 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