INFO: task kworker/u8:2:12613 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:20168 pid:12613 tgid:12613 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 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+0x564/0x660 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+0x49a/0x990 net/core/net_namespace.c:252
 cleanup_net+0x4de/0x820 net/core/net_namespace.c:695
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
 #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90000117ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90000117ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/39:
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:6/1102:
3 locks held by kworker/u8:8/1132:
 #0: ffff88814ccfd138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88814ccfd138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90004e67ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90004e67ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734
4 locks held by kworker/u8:15/3505:
2 locks held by getty/5561:
 #0: ffff88823bf7c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
5 locks held by kworker/1:5/5892:
 #0: ffff8880197be938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff8880197be938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90004ec7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90004ec7ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffff888145f58188 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
 #2: ffff888145f58188 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898
 #3: ffff888038286188 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
 #3: ffff888038286188 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006
 #4: ffff88803849a150 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
 #4: ffff88803849a150 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006
3 locks held by kworker/u8:2/12613:
 #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc9000d68fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc9000d68fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8e856620 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669
2 locks held by udevd/14577:
4 locks held by udevd/15425:
 #0: ffff888058c7a838 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb8/0xe20 fs/seq_file.c:182
 #1: ffff888036802478 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
 #2: ffff88803c3403c8 (kn->active#20){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88803c3403c8 (kn->active#20){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
 #3: ffff888038286188 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline]
 #3: ffff888038286188 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by syz.4.4159/16124:
4 locks held by syz.4.4159/16126:
2 locks held by syz.3.4166/16148:
1 lock held by syz.2.4170/16150:
 #0: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x37d/0x1df0 drivers/net/tun.c:3078
2 locks held by syz.2.4170/16152:
 #0: ffffffff8e847998 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5f1/0x790 net/socket.c:1337
 #1: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:579
1 lock held by syz.2.4170/16154:
 #0: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8e863538 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50 net/ipv4/devinet.c:1120

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 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+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5164 Comm: klogd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__pick_first_entity kernel/sched/fair.c:876 [inline]
RIP: 0010:__pick_eevdf+0x57/0x8d0 kernel/sched/fair.c:947
Code: 80 3c 18 00 74 05 e8 58 89 8c 00 48 8b 45 48 48 89 44 24 40 48 8d 7d 50 48 89 f8 48 c1 e8 03 80 3c 18 00 74 05 e8 39 89 8c 00 <4c> 8b 65 50 4d 8d 7c 24 f0 4d 85 e4 4d 0f 45 e7 48 8d 7d 58 48 89
RSP: 0018:ffffc90003d6f4d8 EFLAGS: 00000046
RAX: 1ffff110171275da RBX: dffffc0000000000 RCX: 1ca6780222df8100
RDX: ffffc90003d6f7b0 RSI: 0000000000000001 RDI: ffff8880b893aed0
RBP: ffff8880b893ae80 R08: ffffffff8ed63e77 R09: 1ffffffff1dac7ce
R10: dffffc0000000000 R11: ffffffff819254c0 R12: ffff888035499ed0
R13: ffff8880b893ae90 R14: dffffc0000000000 R15: ffff8880b893ae80
FS:  00007f61b5be3c80(0000) GS:ffff888126ef7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000001b4030 CR3: 0000000034f26000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 pick_eevdf kernel/sched/fair.c:1007 [inline]
 pick_next_entity kernel/sched/fair.c:5525 [inline]
 pick_task_fair+0x2fe/0x5c0 kernel/sched/fair.c:8853
 pick_task kernel/sched/core.c:6029 [inline]
 pick_next_task kernel/sched/core.c:6129 [inline]
 __schedule+0x2d42/0x4c20 kernel/sched/core.c:6870
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113
 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 class_preempt_destructor include/linux/preempt.h:470 [inline]
 try_to_wake_up+0x82b/0x12b0 kernel/sched/core.c:4300
 autoremove_wake_function+0x17/0x100 kernel/sched/wait.c:403
 __wake_up_common kernel/sched/wait.c:108 [inline]
 __wake_up_common_lock+0x136/0x1e0 kernel/sched/wait.c:125
 sock_def_readable+0x1fe/0x560 net/core/sock.c:3551
 unix_dgram_sendmsg+0xe08/0x1850 net/unix/af_unix.c:2309
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3c7/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2247
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f61b5d33407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffc781f5370 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f61b5be3c80 RCX: 00007f61b5d33407
RDX: 000000000000007b RSI: 00007ffc781f54b0 RDI: 0000000000000003
RBP: 00007ffc781f58e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffc781f58f8
R13: 00007ffc781f54b0 R14: 0000000000000060 R15: 00007ffc781f54b0
 </TASK>
usb 1-1: async_complete: urb error -104
usb 1-1: async_complete: urb error -104
usb 1-1: async_complete: urb error -104
dummy_hcd dummy_hcd.0: timer fired with no URBs pending?