INFO: task kworker/1:3:5903 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:3 state:D stack:22112 pid:5903 tgid:5903 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 process_one_work kernel/workqueue.c:3288 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/u8:0:15400 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:22328 pid:15400 tgid:15400 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __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:4738 process_one_work kernel/workqueue.c:3288 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: 3 locks held by kworker/0:0/9: 3 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: 4 locks held by kworker/1:0/24: 3 locks held by kworker/0:2/29: 1 lock held by khungtaskd/31: #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:847 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/33: 3 locks held by kworker/u8:3/50: 3 locks held by kworker/u8:5/133: 3 locks held by kworker/u8:7/984: 5 locks held by kworker/R-bat_e/3402: 4 locks held by kworker/u8:8/3483: 3 locks held by kworker/u8:9/3503: 1 lock held by klogd/5179: 2 locks held by udevd/5190: 2 locks held by dhcpcd/5484: 1 lock held by dhcpcd/5485: 2 locks held by crond/5561: 2 locks held by getty/5574: #0: ffff88803294e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5806: 4 locks held by kworker/0:4/5878: 3 locks held by kworker/1:3/5903: #0: ffff88813fe13148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88813fe13148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc90004117c40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc90004117c40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 #2: ffffffff8fbd1088 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/1:4/5904: 3 locks held by kworker/0:5/5909: #0: ffff88813fe11d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88813fe11d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc90004177c40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc90004177c40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 #2: ffffffff8fbd1088 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa5/0xfe0 net/wireless/reg.c:2462 2 locks held by kworker/0:6/5918: 2 locks held by kworker/1:5/5945: 2 locks held by kworker/1:6/5952: 4 locks held by kworker/1:7/8422: 3 locks held by kworker/u8:0/15400: #0: ffff88803183e148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88803183e148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc9000f05fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc9000f05fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 #2: ffffffff8fbd1088 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8fbd1088 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4738 3 locks held by kworker/0:3/19997: 3 locks held by kworker/u8:4/19998: 1 lock held by syz-executor/20013: 5 locks held by syz-executor/20016: 1 lock held by syz-executor/20018: 2 locks held by syz-executor/20022: 1 lock held by kworker/R-wg-cr/20053: #0: ffffffff8e5fcea8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2703 1 lock held by kworker/R-wg-cr/20057: #0: ffffffff8e5fcea8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2761 [inline] #0: ffffffff8e5fcea8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0xc4d/0x1130 kernel/workqueue.c:3623 1 lock held by kworker/1:1/20059: 3 locks held by kworker/1:2/20203: 3 locks held by kworker/u8:6/20421: 2 locks held by kworker/0:8/20464: 6 locks held by syz.1.7861/24481: 3 locks held by syz.9.7867/24494: 3 locks held by kworker/u8:10/24496: 3 locks held by kworker/u8:11/24497: 2 locks held by kworker/u8:12/24498: #0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline] #0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371 #1: ffffc9000d5afc40 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline] #1: ffffc9000d5afc40 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371 3 locks held by kworker/u8:13/24499: 3 locks held by kworker/1:8/24501: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: 3402 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 03/18/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:__dev_queue_xmit+0x92/0x3890 net/core/dev.c:4761 Code: f0 32 7e 89 48 8d 9c 24 00 01 00 00 48 c1 eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 33 48 8d 81 00 fa f9 f9 4a 89 44 33 08 <48> b8 f8 f8 f2 f2 f2 f2 f8 f8 4a 89 44 33 10 4a 89 4c 33 18 48 b8 RSP: 0018:ffffc90000a078a0 EFLAGS: 00000212 RAX: f8f8f8f8f2f2f2f8 RBX: 1ffff92000140f34 RCX: f8f8f8f8f8f8f8f8 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff88803f106c80 RBP: ffffc90000a07b58 R08: ffffffff9011e0b7 R09: 1ffffffff2023c16 R10: dffffc0000000000 R11: fffffbfff2023c17 R12: ffff88803f106c80 R13: ffff88803f106cd8 R14: dffffc0000000000 R15: ffff888054301019 FS: 0000000000000000(0000) GS:ffff888125551000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f521de7fb9f CR3: 000000003369f000 CR4: 0000000000350ef0 Call Trace: dev_queue_xmit include/linux/netdevice.h:3385 [inline] br_dev_queue_push_xmit+0x370/0x4a0 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+0x7ef/0xa30 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+0x14c2/0x1bb0 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/0x31a0 net/core/dev.c:6068 __netif_receive_skb_one_core net/core/dev.c:6179 [inline] __netif_receive_skb net/core/dev.c:6294 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6645 __napi_poll+0xae/0x340 net/core/dev.c:7709 napi_poll net/core/dev.c:7772 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7929 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 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:395 [inline] batadv_tt_local_purge+0x2a7/0x340 net/batman-adv/translation-table.c:1320 batadv_tt_purge+0x35/0x9e0 net/batman-adv/translation-table.c:3514 process_one_work kernel/workqueue.c:3288 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371 rescuer_thread+0x827/0x1130 kernel/workqueue.c:3595 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245