INFO: task kworker/u8:1:13 blocked for more than 143 seconds.
      Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1    state:D stack:20888 pid:13    tgid:13    ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5367 [inline]
 __schedule+0x1b18/0x50e0 kernel/sched/core.c:6748
 __schedule_loop kernel/sched/core.c:6825 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6840
 afs_cell_purge+0x3e3/0x550 fs/afs/cell.c:893
 afs_net_exit+0x50/0x100 fs/afs/main.c:146
 ops_exit_list net/core/net_namespace.c:172 [inline]
 cleanup_net+0x814/0xd60 net/core/net_namespace.c:652
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/13:
 #0: ffff88801baf6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801baf6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
 #1: ffffc90000127c60 (
net_cleanup_work
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
 #2: ffffffff8fec98d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:606
1 lock held by khungtaskd/31:
 #0: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6761
2 locks held by kworker/u8:5/1087:
 #0: ffff8881472c3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff8881472c3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
 #1: ffffc90003fafc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90003fafc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
2 locks held by getty/5587:
 #0: ffff88814c7420a0 (&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+0x53d/0x16b0 drivers/tty/n_tty.c:2211
2 locks held by syz.2.3688/17670:
1 lock held by syz.3.3693/17668:
 #0: ffff8880b8639ad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:603
1 lock held by syz.3.3693/17669:
 #0: ffffffff8eb3fc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
 #0: ffffffff8eb3fc78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998
1 lock held by syz.4.3694/17671:
 #0: ffffffff8eb3fb40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0x1058/0x10a0 kernel/hung_task.c:399
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15268 Comm: kworker/0:0 Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:format_decode+0x46c/0xcb0 lib/vsprintf.c:2684
Code: 8d 7e 01 4c 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 76 06 00 00 45 0f b6 66 01 44 89 ef 44 89 e6 e8 17 cb ac f5 45 38 e5 <0f> b6 c3 40 0f b6 ed 0f 44 e8 89 2c 24 4d 0f 44 f7 49 bc 00 00 00
RSP: 0018:ffffc9000c7b69a0 EFLAGS: 00000283
RAX: 0000000000000002 RBX: 0000000000000008 RCX: 0000000000100000
RDX: ffff888034b21e00 RSI: 0000000000000075 RDI: 000000000000006c
RBP: 0000000000000008 R08: ffffffff8c169839 R09: ffffffff8c169453
R10: 0000000000000002 R11: ffff888034b21e00 R12: 0000000000000075
R13: 000000000000006c R14: ffffffff8c2b70a3 R15: ffffffff8c2b70a4
FS:  0000000000000000(0000) GS:ffff888125224000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f7490048 CR3: 000000003121e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 vsnprintf+0x179/0x1230 lib/vsprintf.c:2793
 sprintf+0xdc/0x130 lib/vsprintf.c:3013
 print_time kernel/printk/printk.c:1381 [inline]
 info_print_prefix+0x16d/0x310 kernel/printk/printk.c:1407
 record_print_text+0x14a/0x430 kernel/printk/printk.c:1456
 printk_get_next_message+0x65b/0x8b0 kernel/printk/printk.c:3006
 console_emit_next_record kernel/printk/printk.c:3074 [inline]
 console_flush_all+0x56b/0xec0 kernel/printk/printk.c:3208
 __console_flush_and_unlock kernel/printk/printk.c:3267 [inline]
 console_unlock+0x151/0x3b0 kernel/printk/printk.c:3307
 vprintk_emit+0x732/0xa10 kernel/printk/printk.c:2432
 dev_vprintk_emit+0x358/0x420 drivers/base/core.c:4891
 dev_printk_emit+0xdf/0x130 drivers/base/core.c:4902
 _dev_info+0x12d/0x180 drivers/base/core.c:4960
 usb_disconnect+0xe7/0x960 drivers/usb/core/hub.c:2298
 hub_port_connect drivers/usb/core/hub.c:5373 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5673 [inline]
 port_event drivers/usb/core/hub.c:5833 [inline]
 hub_event+0x1d2a/0x50f0 drivers/usb/core/hub.c:5915
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>