INFO: task hung in usb_remote_wakeup (8)

Status: auto-obsoleted due to no activity on 2026/08/25 20:52
Subsystems: usb
Labels: prio:high
[Documentation on labels]
First crash: 171d, last: 91d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
1f39ef97 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in usb_remote_wakeup (8) 2026/05/16 05:36 2026/05/16 05:36 2026/05/16 06:06 a15a64a6
Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in usb_remote_wakeup 1 1 2087d 2087d 0/1 auto-closed as invalid on 2021/04/07 18:31
upstream INFO: task hung in usb_remote_wakeup (2) usb 1 syz inconclusive done 9 1833d 2031d 20/29 fixed on 2021/11/10 00:50
linux-6.1 INFO: task hung in usb_remote_wakeup 1 syz 1 23d 23d 0/3 upstream: reported syz repro on 2026/08/04 09:34
upstream INFO: task hung in usb_remote_wakeup (3) usb 1 1 1646d 1646d 0/29 auto-closed as invalid on 2022/05/24 13:32
upstream INFO: task hung in usb_remote_wakeup (5) usb 1 1 1205d 1205d 0/29 auto-obsoleted due to no activity on 2023/08/08 04:40
upstream INFO: task hung in usb_remote_wakeup usb 1 7 2497d 2683d 0/29 auto-closed as invalid on 2020/01/24 14:16
upstream INFO: task hung in usb_remote_wakeup (7) usb 1 2 310d 377d 0/29 auto-obsoleted due to no activity on 2026/01/19 09:40
upstream INFO: task hung in usb_remote_wakeup (4) usb 1 2 1386d 1436d 0/29 auto-obsoleted due to no activity on 2023/02/10 23:06
upstream INFO: task hung in usb_remote_wakeup (6) usb 1 1 693d 693d 0/29 auto-obsoleted due to no activity on 2025/01/01 01:43
linux-4.14 INFO: task hung in usb_remote_wakeup 1 1 2148d 2148d 0/1 auto-closed as invalid on 2021/02/06 13:01

Sample crash report:
INFO: task kworker/u8:1:9227 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1    state:D stack:23640 pid:9227  tgid:9227  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: pm hcd_resume_work
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_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 device_lock include/linux/device.h:895 [inline]
 usb_remote_wakeup+0x23/0x100 drivers/usb/core/hub.c:3886
 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:
6 locks held by kworker/0:1/10:
 #0: ffff888105aa8548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc900000afd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
 #2: ffff88810bfec198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff88810bfec198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff88810bfe9510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
 #3: ffff88810bfe9510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
 #3: ffff88810bfe9510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 #3: ffff88810bfe9510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
 #3: ffff88810bfe9510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2bd2/0x4af0 drivers/usb/core/hub.c:5953
 #4: ffff88810b777e68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
 #4: ffff88810b777e68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 #4: ffff88810b777e68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
 #4: ffff88810b777e68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2bfb/0x4af0 drivers/usb/core/hub.c:5953
 #5: ffffffff8a2f14f0 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x1a5/0x1c60 drivers/usb/core/hub.c:3067
6 locks held by kworker/1:0/23:
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 getty/2916:
 #0: ffff888112fe90a0 (&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
6 locks held by kworker/0:6/8183:
3 locks held by kworker/u8:1/9227:
 #0: ffff888103295148 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc9000430fd18 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
 #2: ffff88810c3f4198
 (
&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
&dev->mutex){....}-{4:4}, at: usb_remote_wakeup+0x23/0x100 drivers/usb/core/hub.c:3886
1 lock held by syz.0.2389/14158:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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: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+0xd25/0x1050 kernel/hung_task.c:515
 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>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10920 Comm: kworker/1:5 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:kasan_byte_accessible+0x18/0x30 mm/kasan/generic.c:212
Code: 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 0f b6 07 <3c> 07 0f 96 c0 e9 0e e5 55 05 66 66 2e 0f 1f 84 00 00 00 00 00 0f
RSP: 0018:ffffc900001a8ca8 EFLAGS: 00000086
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff876b1daa RDI: fffffbfff282ccc5
RBP: ffffffff94166628 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff876b1daa
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8882687d3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2a0a8b CR3: 0000000123532000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 __kasan_check_byte+0x13/0x50 mm/kasan/common.c:573
 kasan_check_byte include/linux/kasan.h:402 [inline]
 lock_acquire kernel/locking/lockdep.c:5842 [inline]
 lock_acquire+0x148/0x380 kernel/locking/lockdep.c:5825
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x135/0x3b0 lib/debugobjects.c:873
 debug_hrtimer_deactivate kernel/time/hrtimer.c:451 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1753 [inline]
 __hrtimer_run_queues+0x395/0xa70 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x397/0x8c0 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x109/0x490 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x8a/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:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2478
Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 98 43 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 66 3e 20 00 48 85 ed 0f 85 27 01 00 00 <e8> 78 43 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc900151275d8 EFLAGS: 00000287
RAX: 00000000000423aa RBX: 0000000000000029 RCX: ffffc900117f4000
RDX: 0000000000100000 RSI: ffffffff819177a4 RDI: ffff888112708000
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92002a24ebd
R13: 0000000000000200 R14: ffff888102e91d00 R15: ffffc900151277a0
 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4913
 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4924
 __dev_printk+0xcb/0x100 drivers/base/core.c:4936
 _dev_info+0xef/0x127 drivers/base/core.c:4982
 usb_disconnect+0xec/0x9a0 drivers/usb/core/hub.c:2327
 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>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/09 06:26 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing bb375c251ab4 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: task hung in usb_remote_wakeup
2026/05/27 20:43 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 4b4362973b6f 769cbc61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in usb_remote_wakeup
* Struck through repros no longer work on HEAD.