INFO: task kworker/0:7:5532 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:7     state:D
 stack:21672 pid:5532  tgid:5532  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event

Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0xf89/0x4840 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7339
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:806
 class_mutex_constructor include/linux/mutex.h:253 [inline]
 usb_audio_probe+0x385/0x3b60 sound/usb/card.c:952
 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
 bus_probe_device+0x64/0x160 drivers/base/bus.c:613
 device_add+0x1210/0x1950 drivers/base/core.c:3706
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
 bus_probe_device+0x64/0x160 drivers/base/bus.c:613
 device_add+0x1210/0x1950 drivers/base/core.c:3706
 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+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 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:
1 lock held by khungtaskd/30:
 #0: 
ffffffff896ddaa0
 (
rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/2923:
 #0: ffff8881128c80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900000452e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
4 locks held by udevd/5186:
 #0: ffff88811fd7dab8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: ffff88813370b480 (&of->mutex){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff88811548b0f8 (kn->active#26){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88811548b0f8 (kn->active#26){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff88811a6231d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
 #3: ffff88811a6231d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
8 locks held by kworker/0:3/5205:
6 locks held by kworker/1:4/5242:
 #0: ffff888105ea8540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277
 #1: ffffc90002bb7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278
 #2: ffff88810c3091d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
 #2: ffff88810c3091d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff88811f7711d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
 #3: ffff88811f7711d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #4: ffff88811ba301a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
 #4: ffff88811ba301a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #5: ffffffff8aa2ddc0 (register_mutex#3){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
 #5: ffffffff8aa2ddc0 (register_mutex#3){+.+.}-{4:4}, at: usb_audio_probe+0x385/0x3b60 sound/usb/card.c:952
4 locks held by udevd/5249:
 #0: ffff8881364031b8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: ffff888112ef0880 (&of->mutex){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff88811aabec38 (kn->active#26){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88811aabec38 (kn->active#26){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff888136e651d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
 #3: ffff888136e651d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/5295:
 #0: ffff888113e0abd8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: ffff888119bda880 (&of->mutex){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff8881130713c8 (kn->active#29){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff8881130713c8 (kn->active#29){.+.+}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff88811c5831d8 (&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:1045 [inline]
, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143
6 locks held by kworker/1:5/5357:
 #0: 
ffff888105ea8540
 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277
 #1: 
ffffc90002e97d18
 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278
 #2: ffff88810c3211d8
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1040 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: 
ffff88811c5831d8
 (
&dev->mutex
){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #4: 
ffff88811ebd11a0
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1040 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #5: 
ffffffff8aa2ddc0
 (
register_mutex
#3
){+.+.}-{4:4}
, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
, at: usb_audio_probe+0x385/0x3b60 sound/usb/card.c:952
6 locks held by kworker/0:7/5532:
 #0: 
ffff888105ea8540
 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277
 #1: ffffc90003157d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278
 #2: 
ffff88810bfb91d8
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1040 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: 
ffff88811a6231d8
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1040 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #4: 
ffff88811c63e1a0
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1040 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #5: 
ffffffff8aa2ddc0
 (
register_mutex
#3){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#3){+.+.}-{4:4}, at: usb_audio_probe+0x385/0x3b60 sound/usb/card.c:952
4 locks held by udevd/5916:
 #0: ffff888119c12bd8
 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: ffff888112581480 (&of->mutex){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff88811548bd28
 (kn->active#26
){++++}-{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: ffff88811e0261d8 (&dev->mutex
){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/6701:
 #0: ffff88810af3f2d8
 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: 
ffff888119323480 (&of->mutex){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff88811f325d28 (kn->active#26){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88811f325d28 (kn->active#26){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff88811f7711d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
 #3: ffff88811f7711d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
6 locks held by kworker/1:8/6877:
 #0: ffff888105ea8540
 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277
 #1: 
ffffc90014e97d18
 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278
 #2: 
ffff88810bfa91d8
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1040 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff888136e651d8 (
&dev->mutex
){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #4: ffff8881149981a0
 (&dev->mutex
){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1076
 #5: ffffffff8aa2ddc0
 (
register_mutex#3
){+.+.}-{4:4}
, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
, at: usb_audio_probe+0x385/0x3b60 sound/usb/card.c:952

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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:162 [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:353 [inline]
 watchdog+0xcb1/0x1030 kernel/hung_task.c:561
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
 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: 5205 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:printk_get_console_flush_type+0x26e/0x470 kernel/printk/internal.h:210
Code: 98 12 21 00 84 db 0f 85 c8 00 00 00 e8 3b 18 21 00 48 8d 7d 02 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 <48> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 c1 01 00 00 c6 45 02 01
RSP: 0018:ffffc90002a7e448 EFLAGS: 00000a06
RAX: 0000000000000004 RBX: 0000000000000000 RCX: ffffc90011a2b000
RDX: 1ffff9200054fc9a RSI: ffffffff8191a765 RDI: ffffc90002a7e4d2
RBP: ffffc90002a7e4d0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff9200054fc94
R13: ffffc90002a7e5c0 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888268687000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555682ab908 CR3: 00000001169a2000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 console_flush_one_record+0xbc/0xe50 kernel/printk/printk.c:3244
 console_flush_all kernel/printk/printk.c:3343 [inline]
 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
 console_unlock+0x103/0x260 kernel/printk/printk.c:3413
 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4930
 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4941
 __dev_printk+0xcb/0x100 drivers/base/core.c:4953
 _dev_err+0xef/0x127 drivers/base/core.c:4996
 parse_uac2_sample_rate_range.cold+0xff/0x134 sound/usb/format.c:472
 parse_audio_format_rates_v2v3+0x2fe/0xf70 sound/usb/format.c:693
 parse_audio_format_ii sound/usb/format.c:851 [inline]
 snd_usb_parse_audio_format.cold+0x48c/0x4cc sound/usb/format.c:872
 snd_usb_get_audioformat_uac12 sound/usb/stream.c:864 [inline]
 __snd_usb_parse_audio_interface+0xa85/0x4710 sound/usb/stream.c:1209
 snd_usb_parse_audio_interface+0x81/0x110 sound/usb/stream.c:1290
 create_standard_audio_quirk+0x6b/0x120 sound/usb/quirks.c:104
 snd_usb_create_quirk sound/usb/quirks.c:544 [inline]
 create_composite_quirk+0x257/0x510 sound/usb/quirks.c:52
 snd_usb_create_quirk+0xad/0xf0 sound/usb/quirks.c:544
 usb_audio_probe+0x969/0x3b60 sound/usb/card.c:1025
 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
 bus_probe_device+0x64/0x160 drivers/base/bus.c:613
 device_add+0x1210/0x1950 drivers/base/core.c:3706
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
 bus_probe_device+0x64/0x160 drivers/base/bus.c:613
 device_add+0x1210/0x1950 drivers/base/core.c:3706
 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+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>