INFO: task kworker/u8:5:137 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:5 state:D stack:22424 pid:137 tgid:137 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound linkwatch_event Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x153e/0x4fe0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 linkwatch_event+0xe/0x60 net/core/link_watch.c:303 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9af/0xee0 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/R-ipv6_:3182 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/R-ipv6_ state:D stack:29464 pid:3182 tgid:3182 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x153e/0x4fe0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] rescuer_thread+0x8a8/0x1210 kernel/workqueue.c:3586 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 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/0:1/10: 3 locks held by kworker/u8:0/12: 1 lock held by khungtaskd/30: #0: ffffffff8e75dde0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75dde0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75dde0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/0:2/87: 3 locks held by kworker/u8:5/137: #0: ffff88813ff4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc90002e57c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8fbd6148 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 3 locks held by kworker/u8:6/267: 3 locks held by kworker/u8:8/1926: 3 locks held by kworker/R-ipv6_/3182: #0: ffff888032af1948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000be0fc00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8fbd6148 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8fbd6148 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734 4 locks held by kworker/R-bat_e/3408: 4 locks held by kworker/u8:9/3459: 4 locks held by kworker/u8:11/3545: 3 locks held by kworker/u8:12/3604: 3 locks held by kworker/u8:13/4364: 4 locks held by kworker/u8:14/4909: 1 lock held by klogd/5189: 1 lock held by udevd/5200: 2 locks held by crond/5569: 2 locks held by getty/5581: #0: ffff8880377630a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5824: 1 lock held by syz-executor/5830: 4 locks held by kworker/1:3/5831: 7 locks held by kworker/u9:4/5838: #0: ffff88806a162148 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000423fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffff888038700ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 #3: ffff8880387000c0 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x8a3/0xed0 net/bluetooth/hci_sync.c:5734 #4: ffffffff8fd62588 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline] #4: ffffffff8fd62588 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x340 net/bluetooth/hci_conn.c:1342 #5: ffff88802678c338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 net/bluetooth/l2cap_core.c:1763 #6: ffffffff8e764078 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #6: ffffffff8e764078 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 3 locks held by kworker/1:8/5915: #0: ffff88807b77c548 ((wq_completion)wg-kex-wg2#8){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000464fc40 ((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+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffff88808c11c890 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_begin_session+0x36/0xbd0 drivers/net/wireguard/noise.c:822 3 locks held by kworker/0:6/5924: #0: ffff88807ecd4548 ((wq_completion)wg-kex-wg1#2){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc900046bfc40 ((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+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffff88805ca96648 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_begin_session+0x36/0xbd0 drivers/net/wireguard/noise.c:822 2 locks held by syz.2.5/5930: 2 locks held by syz.2.5/5933: 4 locks held by kworker/1:6/11425: 1 lock held by syz.2.1945/12130: 3 locks held by kworker/0:10/12482: #0: ffff88813ff0d548 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000c69fc40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8fbd6148 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa5/0xf50 net/wireless/reg.c:2462 2 locks held by kworker/u8:1/12650: 1 lock held by syz.2.2110/12766: 4 locks held by kworker/u8:2/12775: 4 locks held by syz.4.2115/12813: 4 locks held by kworker/u8:4/12812: 3 locks held by rm/12816: 4 locks held by kworker/u8:7/12817: #0: ffff88807d898148 ((wq_completion)wg-kex-wg1){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc90002e97c40 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffff888036e49348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x12f/0x830 drivers/net/wireguard/noise.c:529 #3: ffff88805ca96648 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x140/0x830 drivers/net/wireguard/noise.c:530 4 locks held by kworker/u8:10/12818: 3 locks held by syz-executor/12819: 3 locks held by kworker/u8:15/12820: 3 locks held by kworker/u8:16/12821: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 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+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 3408 Comm: kworker/R-bat_e Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:unwind_next_frame+0x484/0x23c0 arch/x86/kernel/unwind_orc.c:520 Code: d2 84 c0 48 0f 45 d1 48 89 15 a8 ab a8 11 48 85 d2 0f 84 40 02 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 66 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f RSP: 0018:ffffc90000a07138 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: ffffffff902aa1e0 RCX: ffffffff902aa1e4 RDX: ffffffff90a847d6 RSI: ffffffff90a847d6 RDI: ffffffff8c0952a0 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e75dde0 R10: ffffc90000a07258 R11: ffffffff81aeea40 R12: ffffffff90a847da R13: ffffffff90a847db R14: ffffc90000a07208 R15: ffffffff902aa1e0 FS: 0000000000000000(0000) GS:ffff8881253a1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbb8806a008 CR3: 000000000e54a000 CR4: 00000000003526f0 Call Trace: 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 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2627 [inline] slab_free mm/slub.c:6013 [inline] kmem_cache_free+0x190/0x5c0 mm/slub.c:6126 packet_rcv+0x175/0x1720 net/packet/af_packet.c:2223 dev_queue_xmit_nit+0xa39/0xad0 net/core/dev.c:2600 xmit_one net/core/dev.c:3862 [inline] dev_hard_start_xmit+0x1c1/0x7f0 net/core/dev.c:3882 __dev_queue_xmit+0x14ed/0x32b0 net/core/dev.c:4832 dev_queue_xmit include/linux/netdevice.h:3387 [inline] br_dev_queue_push_xmit+0x6d2/0x8b0 net/bridge/br_forward.c:53 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:318 br_nf_post_routing+0xb66/0xfe0 net/bridge/br_netfilter_hooks.c:966 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+0x23e/0x3f0 include/linux/netfilter.h:316 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:1167 [inline] br_nf_forward_finish+0xa5e/0xe90 net/bridge/br_netfilter_hooks.c:662 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:318 br_nf_forward_ip+0x647/0x7e0 net/bridge/br_netfilter_hooks.c:716 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+0x23e/0x3f0 include/linux/netfilter.h:316 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 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+0x989/0x1520 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+0x72/0x370 net/core/dev.c:6265 process_backlog+0x54e/0x1340 net/core/dev.c:6617 __napi_poll+0xae/0x320 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x696/0xe30 net/core/dev.c:7896 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:626 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:398 [inline] batadv_tt_local_purge+0x2a7/0x340 net/batman-adv/translation-table.c:1315 batadv_tt_purge+0x35/0x9e0 net/batman-adv/translation-table.c:3509 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] rescuer_thread+0x8a8/0x1210 kernel/workqueue.c:3586 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245