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INFO: task hung in usb_stor_disconnect (2)

Status: auto-obsoleted due to no activity on 2026/05/26 16:00
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
First crash: 116d, last: 116d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
0b389cf5-49ca-4bff-8fa3-0723d5c3a48a assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in usb_stor_disconnect (2) 2026/05/21 17:21 2026/05/21 17:21 2026/05/21 17:52 d57425845dbe663f86e1e54a4997e95bd557b624

			
		
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in usb_stor_disconnect usb-storage 1 40 610d 619d 0/29 auto-obsoleted due to no activity on 2024/12/29 00:28

Sample crash report:
INFO: task kworker/0:2:2544 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2     state:D
 stack:21256 pid:2544  tgid:2544  ppid:2      task_flags:0x4288060 flags:0x00080000
Workqueue: usb_hub_wq hub_event

Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0xeb1/0x41f0 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7004
 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121
 __flush_work+0x7c7/0xcb0 kernel/workqueue.c:4327
 __cancel_work_sync kernel/workqueue.c:4447 [inline]
 cancel_delayed_work_sync+0xd1/0xf0 kernel/workqueue.c:4521
 quiesce_and_remove_host drivers/usb/storage/usb.c:939 [inline]
 usb_stor_disconnect+0xc5/0x270 drivers/usb/storage/usb.c:1186
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:573 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:565
 __device_release_driver drivers/base/dd.c:1284 [inline]
 device_release_driver_internal+0x42e/0x600 drivers/base/dd.c:1307
 bus_remove_device+0x22f/0x440 drivers/base/bus.c:616
 device_del+0x376/0x9b0 drivers/base/core.c:3878
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1418
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5407 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
 process_scheduled_works kernel/workqueue.c:3358 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
 kthread+0x370/0x450 kernel/kthread.c:467
 ret_from_fork+0x6c3/0xcb0 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/0:0/9:
2 locks held by kworker/u8:0/12:
 #0: ffff8881000ac148
 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc900000cfd18 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
1 lock held by kworker/R-mm_pe/13:
3 locks held by kworker/1:0/23:
2 locks held by kworker/1:1/28:
 #0: ffff88810006b548
 ((wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc900001e7d18
 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
1 lock held by khungtaskd/30:
 #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:2/37:
 #0: 
ffff8881000ac948 ((wq_completion)events_unbound#2){+.+.}-{0:0}
, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: 
ffffc90000277d18 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
5 locks held by kworker/0:2/2544:
 #0: ffff888105e99148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: 
ffffc90004befd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
 #2: ffff88810b7b9198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff88810b7b9198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff88813df19198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #3: ffff88813df19198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336
 #4: ffff888120f3e160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #4: ffff888120f3e160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1106 [inline]
 #4: ffff888120f3e160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xaa/0x600 drivers/base/dd.c:1304
1 lock held by udevd/2851:
 #0: ffff888101298188
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185
2 locks held by getty/2914:
 #0: 
ffff888112a140a0
 (
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: 
ffffc900000432f0 (
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by udevd/5198:
 #0: 
ffff888101298188
 (
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185
5 locks held by kworker/0:3/5218:
4 locks held by udevd/5235:
 #0: 
ffff888133eb1668
 (
&p->lock){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: 
ffff888134873888
 (
&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: 
ffff888133092698
 (
kn->active
#9
){++++}-{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: 
ffff888121439198
 (
&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
4 locks held by udevd/5236:
 #0: 
ffff888133eb1c30
 (
&p->lock){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: 
ffff8881134ca488
 (

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/25 15:55 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 6de23f81a5e0 94a9671e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: task hung in usb_stor_disconnect
* Struck through repros no longer work on HEAD.