INFO: task kworker/0:1:10 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1     state:D
 stack:21632 pid:10    tgid:10    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event

Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0xeb0/0x3e50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:6964
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 uevent_net_broadcast_untagged lib/kobject_uevent.c:317 [inline]
 kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline]
 kobject_uevent_env+0xba8/0x18b0 lib/kobject_uevent.c:608
 device_add+0x116e/0x1950 drivers/base/core.c:3670
 usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695
 hub_port_connect drivers/usb/core/hub.c:5567 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
 kthread+0x3b3/0x730 kernel/kthread.c:463
 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/0:1/10:
10 locks held by kworker/1:0/23:
1 lock held by khungtaskd/30:
 #0: 
ffffffff894da3a0
 (
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:7/332:
2 locks held by getty/2919:
 #0: 
ffff8881127e40a0
 (
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: 
ffffc900000452f0
 (
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by sshd-session/2955:
4 locks held by udevd/5197:
 #0: ffff888120417668
 (
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182
 #1: 
ffff88811f686488
 (
&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff88813e333c38
 (
kn->active#23
){++++}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: 
ffff88813a556198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:900 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
7 locks held by kworker/1:2/5205:
 #0: ffff888100ed2d48
 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
 #1: ffffc900021afca8
 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
 #2: 
ffff88810a71e198
 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff88813a556198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1006
 #4: 
ffff88811d395160
 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1006
 #5: ffffffff8a7f2808
 (
register_mutex
#3
){+.+.}-{4:4}
, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
, at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950
 #6: 
ffff8881f57390d8
 (
&rq->__lock
){-.-.}-{2:2}
, at: raw_spin_rq_lock_nested kernel/sched/core.c:639 [inline]
, at: raw_spin_rq_lock kernel/sched/sched.h:1580 [inline]
, at: rq_lock kernel/sched/sched.h:1907 [inline]
, at: __schedule+0x2c5/0x3e50 kernel/sched/core.c:6772
9 locks held by kworker/1:3/5219:
4 locks held by udevd/5232:
 #0: ffff888104ebd0a0
 (
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182
 #1: 
ffff888121637c88
 (
&of->mutex#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff8881141e54b8
 (kn->active
#23
){++++}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff888122d24198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:900 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by kworker/1:5/5238:
 #0: 
ffff888100ed2d48 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
 #1: ffffc9000225fca8
 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
 #2: 
ffff88810a36e198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
1 lock held by syz.3.1529/10520:
2 locks held by syz.4.1535/10534:
 #0: 
ffff88810a37cdc0
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: __device_driver_lock drivers/base/dd.c:1104 [inline]
, at: device_release_driver_internal+0xaa/0x600 drivers/base/dd.c:1302
 #1: ffffffff8abb6b48
 (
uevent_sock_mutex
){+.+.}-{4:4}
, at: uevent_net_broadcast_untagged lib/kobject_uevent.c:317 [inline]
, at: kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline]
, at: kobject_uevent_env+0xba8/0x18b0 lib/kobject_uevent.c:608
8 locks held by syz.2.1536/10536:
1 lock held by syz.1.1537/10538:
 #0: ffffffff8abb6b48
 (uevent_sock_mutex
){+.+.}-{4:4}
, at: uevent_net_broadcast_untagged lib/kobject_uevent.c:317 [inline]
, at: kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline]
, at: kobject_uevent_env+0xba8/0x18b0 lib/kobject_uevent.c:608
2 locks held by syz-executor/10540:
 #0: 
ffffffff8a8b49b0
 (
pernet_ops_rwsem){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10550:
 #0: 
ffffffff8a8b49b0 (
pernet_ops_rwsem){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10562:
 #0: ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: ffffffff8a8ccfe8
 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10564:
 #0: ffffffff8a8b49b0
 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10567:
 #0: ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (
rtnl_mutex){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10590:
 #0: 
ffffffff8a8b49b0
 (
pernet_ops_rwsem){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: ffffffff8a8ccfe8
 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10600:
 #0: ffffffff8a8b49b0
 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10612:
 #0: 
ffffffff8a8b49b0
 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (
rtnl_mutex){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10614:
 #0: ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: ffffffff8a8ccfe8
 (rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10616:
 #0: ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10641:
 #0: 
ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10651:
 #0: 
ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10663:
 #0: ffffffff8a8b49b0
 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8
 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10665:
 #0: ffffffff8a8b49b0
 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: ffffffff8a8ccfe8
 (rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096
2 locks held by syz-executor/10667:
 #0: 
ffffffff8a8b49b0
 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x41e/0x780 net/core/net_namespace.c:577
 #1: 
ffffffff8a8ccfe8 (
rtnl_mutex){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2096

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
 kthread+0x3b3/0x730 kernel/kthread.c:463
 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
cdc_wdm 4-1:1.0: Stall on int endpoint
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9242 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue:  0x0 (events)
RIP: 0010:__sanitizer_cov_trace_switch+0x45/0x90 kernel/kcov.c:351
Code: 63 77 48 48 83 f8 08 74 63 41 be 03 00 00 00 48 83 f8 10 75 29 4c 8b 6d 00 31 db 4d 85 ed 74 1e 48 8b 74 dd 10 48 8b 4c 24 28 <4c> 89 e2 4c 89 f7 48 83 c3 01 e8 8c fd ff ff 49 39 dd 75 e2 5b 5d
RSP: 0018:ffffc900001a8020 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffffffff8750fd4e
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff888122e71d40
RBP: ffffffff88662cc0 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 00000000003a3450 R12: 0000000000000000
R13: 0000000000000008 R14: 0000000000000001 R15: 1ffff92000035016
FS:  0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557bd2b11880 CR3: 00000001177b2000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 vsnprintf+0x1fe/0x1240 lib/vsprintf.c:2891
 sprintf+0xcc/0x100 lib/vsprintf.c:3110
 print_time kernel/printk/printk.c:1357 [inline]
 info_print_prefix+0x25a/0x350 kernel/printk/printk.c:1383
 record_print_text+0x143/0x3c0 kernel/printk/printk.c:1432
 printk_get_next_message+0x2d1/0x6c0 kernel/printk/printk.c:3018
 console_emit_next_record kernel/printk/printk.c:3083 [inline]
 console_flush_one_record+0x67c/0xe50 kernel/printk/printk.c:3215
 console_flush_all kernel/printk/printk.c:3289 [inline]
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0x103/0x260 kernel/printk/printk.c:3359
 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426
 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4914
 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4925
 __dev_printk+0xcb/0x100 drivers/base/core.c:4937
 _dev_err+0xef/0x127 drivers/base/core.c:4980
 wdm_int_callback+0x981/0xa80 drivers/usb/class/cdc-wdm.c:270
 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657
 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
 dummy_timer+0xd85/0x3670 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x516/0x990 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
 handle_softirqs+0x1dd/0x8f0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch.isra.0+0x160/0x700 kernel/sched/core.c:5118
Code: 8d 7b 18 31 f6 e8 20 d0 0a 00 31 f6 48 89 df e8 d6 f9 ff ff 48 89 df e8 1e c3 d2 05 e8 09 be 35 00 fb 49 8d bc 24 40 15 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 5a
RSP: 0018:ffffc9000191fbe8 EFLAGS: 00000206
RAX: 0000000000000359 RBX: ffff8881f57390c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff88dec6f5 RDI: ffff888122e73280
RBP: ffffc9000191fc30 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888122e71d40
R13: ffff8881176cd7c0 R14: 0000000000000000 R15: 0000000000000000
 context_switch kernel/sched/core.c:5263 [inline]
 __schedule+0xeb8/0x3e50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:6964
 worker_thread+0x526/0xe40 kernel/workqueue.c:3436
 kthread+0x3b3/0x730 kernel/kthread.c:463
 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>