INFO: task kworker/u8:5:183 blocked for more than 143 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5 state:D stack:25448 pid:183 tgid:183 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776
caif_exit_net+0x64/0x3c0 net/caif/caif_dev.c:528
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
cleanup_net+0x41b/0x830 net/core/net_namespace.c:696
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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 init/1:
1 lock held by kthreadd/2:
4 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c94a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c94a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c94a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/36:
1 lock held by khugepaged/38:
3 locks held by kworker/1:1/48:
4 locks held by kworker/u8:3/50:
#0: ffff888022b6e948 ((wq_completion)wg-kex-wg2#3){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90000bb7c90 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff8880781f9308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x610 drivers/net/wireguard/noise.c:529
#3: ffff88803203b4c0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x610 drivers/net/wireguard/noise.c:530
3 locks held by kworker/u8:4/79:
4 locks held by kworker/1:2/89:
4 locks held by kworker/u8:5/183:
#0: ffff88801badf148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90002fd7c90 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff9012b890 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x830 net/core/net_namespace.c:670
#3: ffffffff90142068 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x64/0x3c0 net/caif/caif_dev.c:528
5 locks held by kworker/1:3/981:
3 locks held by kworker/u8:6/1017:
3 locks held by kworker/u8:7/1056:
3 locks held by kworker/u8:8/1108:
2 locks held by kworker/u8:9/1114:
#0: ffff8881456a3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc900040dfc90 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
3 locks held by kworker/u8:10/1139:
3 locks held by kworker/u8:11/3433:
4 locks held by kworker/u8:12/3485:
#0: ffff8880762d6148 ((wq_completion)wg-kex-wg2#5){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000bf17c90 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff888020ad1308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x610 drivers/net/wireguard/noise.c:529
#3: ffff888034741708 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x610 drivers/net/wireguard/noise.c:530
2 locks held by kworker/u8:14/3821:
3 locks held by kworker/u8:15/3874:
2 locks held by kworker/u8:16/3977:
#0: ffff88813ff69148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000cd57c90 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
3 locks held by kworker/u8:17/4247:
1 lock held by klogd/5192:
2 locks held by udevd/5203:
1 lock held by dhcpcd/5497:
3 locks held by crond/5575:
4 locks held by sshd-session/5820:
2 locks held by syz-executor/5821:
3 locks held by kworker/1:4/5848:
#0: ffff88813ff56948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc900041bfc90 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90142068 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x1190 net/wireless/reg.c:2453
4 locks held by kworker/1:5/5924:
4 locks held by kworker/1:6/5958:
3 locks held by kworker/u8:18/6631:
#0: ffff88814cd04948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90004c8fc90 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90142068 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff90142068 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734
5 locks held by kworker/1:7/7671:
4 locks held by kworker/u8:19/8132:
#0: ffff8880285d1148 ((wq_completion)wg-kex-wg1#3){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9001967fc90 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff888029a49308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x610 drivers/net/wireguard/noise.c:529
#3: ffff88803203a0f0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x610 drivers/net/wireguard/noise.c:530
3 locks held by kworker/1:8/8267:
#0: ffff88813ff55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90018967c90 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90142068 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/1:9/8768:
2 locks held by syz.2.882/9450:
1 lock held by syz.3.874/9458:
#0: ffff88807a2bb440 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:391 [inline]
#0: ffff88807a2bb440 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm kernel/exit.c:557 [inline]
#0: ffff88807a2bb440 (&mm->mmap_lock){++++}-{4:4}, at: do_exit+0x6c5/0x2bd0 kernel/exit.c:959
6 locks held by syz.1.876/9459:
2 locks held by syz.1.876/9460:
3 locks held by syz.0.877/9461:
6 locks held by syz.0.877/9462:
1 lock held by syz.0.877/9464:
#0: ffff88807a2b9bc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:391 [inline]
#0: ffff88807a2b9bc0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm kernel/exit.c:557 [inline]
#0: ffff88807a2b9bc0 (&mm->mmap_lock){++++}-{4:4}, at: do_exit+0x6c5/0x2bd0 kernel/exit.c:959
3 locks held by modprobe/9463:
4 locks held by kworker/u8:20/9465:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
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+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246