INFO: task kworker/0:7:6614 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:7     state:D stack:21336 pid:6614  tgid:6614  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 usb_audio_probe+0x63a/0x2380
 usb_probe_interface+0x659/0xc70
 really_probe+0x267/0xaf0
 __driver_probe_device+0x1ef/0x380
 driver_probe_device+0x4f/0x240
 __device_attach_driver+0x279/0x430
 bus_for_each_drv+0x258/0x2f0
 __device_attach+0x2c5/0x450
 device_initial_probe+0xa1/0xd0
 bus_probe_device+0x12a/0x220
 device_add+0x7e9/0xbb0
 usb_set_configuration+0x1a87/0x2110
 usb_generic_driver_probe+0x8d/0x150
 usb_probe_device+0x1c4/0x3b0
 really_probe+0x267/0xaf0
 __driver_probe_device+0x1ef/0x380
 driver_probe_device+0x4f/0x240
 __device_attach_driver+0x279/0x430
 bus_for_each_drv+0x258/0x2f0
 __device_attach+0x2c5/0x450
 device_initial_probe+0xa1/0xd0
 bus_probe_device+0x12a/0x220
 device_add+0x7e9/0xbb0
 usb_new_device+0xa08/0x16f0
 hub_event+0x2a1c/0x4f30
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
6 locks held by kworker/0:2/851:
 #0: ffff8881688d2540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90004fe7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff8881714071d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30
 #3: ffff8881105651d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #4: ffff8880204e31a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #5: ffffffff8fd36c00 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x63a/0x2380
6 locks held by kworker/0:3/5426:
 #0: ffff8881688d2540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90003defc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff8881710b61d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30
 #3: ffff888021bdb1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #4: ffff888020ce91a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #5: ffffffff8fd36c00 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x63a/0x2380
2 locks held by getty/5437:
 #0: ffff88810ee6d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
6 locks held by kworker/1:7/5723:
6 locks held by kworker/0:7/6614:
 #0: ffff8881688d2540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90003ccfc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff8881712061d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30
 #3: ffff888113ad71d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #4: ffff8881128e41a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #5: ffffffff8fd36c00 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x63a/0x2380
4 locks held by udevd/15015:
 #0: ffff8881b18da098 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff88810da0e080 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420
 #2: ffff88819e40fe18 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420
 #3: ffff8881a71d01d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
4 locks held by udevd/15032:
 #0: ffff88816f81cbd8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff88810f6dd880 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420
 #2: ffff8881913690f8 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420
 #3: ffff888113ad71d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
4 locks held by udevd/15071:
 #0: ffff88810ccbbcf8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff8880120b9c80 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420
 #2: ffff88810d395788 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420
 #3: ffff8881105651d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
4 locks held by udevd/17887:
 #0: ffff88816dbb3bd8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10
 #1: ffff888172919480 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420
 #2: ffff88810d85bf08 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420
 #3: ffff888021bdb1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
1 lock held by syz-executor/18131:
 #0: ffffffff8e9630a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by syz.5.2813/18237:
 #0: ffff8881712061d8 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770
1 lock held by syz.2.2969/18878:
 #0: ffff8881712061d8 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5723 Comm: kworker/1:7 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: usb_hub_wq hub_event
RIP: 0010:__snd_usb_parse_audio_interface+0x37ed/0x4cc0
Code: 41 89 dc 4c 03 a4 24 f0 00 00 00 4c 89 e0 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 df 00 00 00 ff c3 45 88 3c 24 44 8b 7c 24 20 <bf> 01 00 00 00 44 89 f6 e8 c6 16 74 f8 89 df 44 89 fe e8 3c 14 74
RSP: 0018:ffffc9000640ea00 EFLAGS: 00000246
RAX: ffffffff89518dd1 RBX: 0000000000000000 RCX: 0000000000100000
RDX: ffffc9002c6c4000 RSI: 00000000000fffff RDI: 0000000000100000
RBP: ffffc9000640ec00 R08: ffffffff9030b2f7 R09: 1ffffffff206165e
R10: dffffc0000000000 R11: fffffbfff206165f R12: 0000000000000000
R13: dffffc0000000000 R14: 00000000000007fb R15: 0000000000000006
FS:  0000000000000000(0000) GS:ffff8882a9291000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055daf1b4a4f0 CR3: 0000000177cd6000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 snd_usb_parse_audio_interface+0x39/0xc0
 snd_usb_create_stream+0x3d2/0x640
 usb_audio_probe+0x1876/0x2380
 usb_probe_interface+0x659/0xc70
 really_probe+0x267/0xaf0
 __driver_probe_device+0x1ef/0x380
 driver_probe_device+0x4f/0x240
 __device_attach_driver+0x279/0x430
 bus_for_each_drv+0x258/0x2f0
 __device_attach+0x2c5/0x450
 device_initial_probe+0xa1/0xd0
 bus_probe_device+0x12a/0x220
 device_add+0x7e9/0xbb0
 usb_set_configuration+0x1a87/0x2110
 usb_generic_driver_probe+0x8d/0x150
 usb_probe_device+0x1c4/0x3b0
 really_probe+0x267/0xaf0
 __driver_probe_device+0x1ef/0x380
 driver_probe_device+0x4f/0x240
 __device_attach_driver+0x279/0x430
 bus_for_each_drv+0x258/0x2f0
 __device_attach+0x2c5/0x450
 device_initial_probe+0xa1/0xd0
 bus_probe_device+0x12a/0x220
 device_add+0x7e9/0xbb0
 usb_new_device+0xa08/0x16f0
 hub_event+0x2a1c/0x4f30
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
