INFO: task kworker/u8:14:13080 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:14 state:D stack:22312 pid:13080 tgid:13080 ppid:2 task_flags:0x4208160 flags:0x00080000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 rxrpc_destroy_all_calls+0x55e/0x660 net/rxrpc/call_object.c:757 rxrpc_exit_net+0x6f/0xc0 net/rxrpc/net_ns.c:112 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x497/0x990 net/core/net_namespace.c:252 cleanup_net+0x4d8/0x820 net/core/net_namespace.c:695 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 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 khungtaskd/31: #0: ffffffff8dd3b220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8dd3b220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8dd3b220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/1:1/61: #0: ffff8881442e3548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8881442e3548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000212fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000212fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888144b60198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888144b60198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff888144b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff888144b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x628/0x4a20 drivers/usb/core/hub.c:5951 2 locks held by getty/5603: #0: ffff88814dbb80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by kworker/u8:9/11580: #0: ffff888020380148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020380148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90003b2fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90003b2fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 3 locks held by kworker/u8:14/13080: #0: ffff88801ae9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801ae9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90004887bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90004887bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f0c1350 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669 2 locks held by kworker/u8:16/13084: #0: ffff888020380148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020380148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc900053ffbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc900053ffbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 4 locks held by syz.2.3526/19594: #0: ffffffff8e9856d0 (minor_rwsem#2){++++}-{4:4}, at: usb_open+0x30/0x1e0 drivers/usb/core/file.c:38 #1: ffffffff8ea0d748 (wdm_mutex){+.+.}-{4:4}, at: wdm_open+0x57/0x550 drivers/usb/class/cdc-wdm.c:710 #2: ffff888144b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #2: ffff888144b63518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_port_resume+0x272/0x1cc0 drivers/usb/core/hub.c:3809 #3: ffff888142f31768 (hcd->address0_mutex){+.+.}-{4:4}, at: usb_reset_and_verify_device+0x372/0x1a80 drivers/usb/core/hub.c:6203 1 lock held by syz.1.3539/19652: 1 lock held by syz.3.3542/19661: ============================================= NMI backtrace for cpu 0 CPU: 0 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+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 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: 5955 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: events_power_efficient wg_ratelimiter_gc_entries RIP: 0010:__lock_acquire+0xa38/0xd20 kernel/locking/lockdep.c:5233 Code: c0 0d 00 75 19 90 48 c7 c7 72 68 6f 8d 48 c7 c6 2c 25 5f 8d e8 29 c1 e5 ff 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 48 83 78 40 00 <0f> 84 8c 02 00 00 41 8b 46 20 25 ff 1f 00 00 48 0f a3 05 a1 26 b6 RSP: 0018:ffffc9000528f8e8 EFLAGS: 00000086 RAX: ffffffff92f92f38 RBX: 0000000000000002 RCX: 00000000d2838ef7 RDX: 00000000fdf804b8 RSI: 00000000b1177cf2 RDI: ffff88802be6bc80 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff86311d1d R10: dffffc0000000000 R11: fffffbfff1d0384d R12: 00000000cb8ffaab R13: ffff88802be6c7b0 R14: ffff88802be6c800 R15: 3028545cd2838ef7 FS: 0000000000000000(0000) GS:ffff888126478000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000002cf030 CR3: 000000007e2c8000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] wg_ratelimiter_gc_entries+0x5d/0x450 drivers/net/wireguard/ratelimiter.c:63 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245