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INFO: task hung in usb_audio_probe

Status: premoderation: reported on 2026/03/17 07:22
Reported-by: syzbot+f811d213c66df0722b78@syzkaller.appspotmail.com
First crash: 12d, last: 12d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in usb_audio_probe (2) sound 1 1 648d 648d 0/29 auto-obsoleted due to no activity on 2024/09/17 10:08
upstream INFO: task hung in usb_audio_probe sound 1 1 1682d 1682d 0/29 auto-closed as invalid on 2021/11/18 21:08
upstream INFO: task hung in usb_audio_probe (4) sound 1 1 303d 303d 0/29 auto-obsoleted due to no activity on 2025/08/28 06:21
upstream INFO: task hung in usb_audio_probe (3) sound 1 3 417d 537d 0/29 auto-obsoleted due to no activity on 2025/05/06 03:30

Sample crash report:
INFO: task kworker/1:0:31 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:0     state:D stack:0     pid:31    tgid:31    ppid:2      flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864
 __schedule_loop kernel/sched/core.c:7945 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7960
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8017
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 usb_audio_probe+0x39d/0x1d60 sound/usb/card.c:887
 usb_probe_interface+0x6ac/0xc00 drivers/usb/core/driver.c:400
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_set_configuration+0x1acf/0x20b0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254
 usb_probe_device+0x1d4/0x380 drivers/usb/core/driver.c:295
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_new_device+0x9f8/0x15b0 drivers/usb/core/hub.c:2703
 hub_port_connect drivers/usb/core/hub.c:5574 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5714 [inline]
 port_event drivers/usb/core/hub.c:5878 [inline]
 hub_event+0x30c6/0x4700 drivers/usb/core/hub.c:5960
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
 kthread+0x2c6/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/0:4:443 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4     state:D stack:0     pid:443   tgid:443   ppid:2      flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864
 __schedule_loop kernel/sched/core.c:7945 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7960
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8017
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 usb_audio_probe+0x39d/0x1d60 sound/usb/card.c:887
 usb_probe_interface+0x6ac/0xc00 drivers/usb/core/driver.c:400
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_set_configuration+0x1acf/0x20b0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254
 usb_probe_device+0x1d4/0x380 drivers/usb/core/driver.c:295
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_new_device+0x9f8/0x15b0 drivers/usb/core/hub.c:2703
 hub_port_connect drivers/usb/core/hub.c:5574 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5714 [inline]
 port_event drivers/usb/core/hub.c:5878 [inline]
 hub_event+0x30c6/0x4700 drivers/usb/core/hub.c:5960
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
 kthread+0x2c6/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/0:5:562 blocked for more than 124 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:5     state:D stack:0     pid:562   tgid:562   ppid:2      flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864
 __schedule_loop kernel/sched/core.c:7945 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7960
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8017
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 usb_audio_probe+0x39d/0x1d60 sound/usb/card.c:887
 usb_probe_interface+0x6ac/0xc00 drivers/usb/core/driver.c:400
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_set_configuration+0x1acf/0x20b0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254
 usb_probe_device+0x1d4/0x380 drivers/usb/core/driver.c:295
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_new_device+0x9f8/0x15b0 drivers/usb/core/hub.c:2703
 hub_port_connect drivers/usb/core/hub.c:5574 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5714 [inline]
 port_event drivers/usb/core/hub.c:5878 [inline]
 hub_event+0x30c6/0x4700 drivers/usb/core/hub.c:5960
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
 kthread+0x2c6/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 e9db8685c400c70f0098c2bc673af807e74041bb
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xdad/0xf00 kernel/hung_task.c:423
 kthread+0x2c6/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 460 Comm: kworker/1:4 Not tainted syzkaller #0 e9db8685c400c70f0098c2bc673af807e74041bb
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp4+0x3a/0x90 kernel/kcov.c:288
Code: dc 46 7d 7e 65 8b 0d dd 46 7d 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba ec 0b 00 00 00 74 52 8b 8a c8 0b 00 00 <83> f9 03 75 47 48 8b 8a d0 0b 00 00 44 8b 8a cc 0b 00 00 49 c1 e1
RSP: 0018:ffffc9000c22ec30 EFLAGS: 00000246
RAX: ffffffff846590af RBX: 00000000000007fb RCX: 0000000000000002
RDX: ffff888116c12600 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000c22ec30 R08: ffffffff8109ba2a R09: ffffffff8109ba2a
R10: ffffffff8158c8e6 R11: ffffffff813c95a4 R12: 0000000000000001
R13: ffff88811af88007 R14: 00000000000007fb R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3f90fc0e9c CR3: 00000001027ae000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: fffffffffffffffc DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __snd_usb_parse_audio_interface+0x297f/0x47d0 sound/usb/stream.c:-1
 snd_usb_parse_audio_interface+0x3e/0xd0 sound/usb/stream.c:1280
 snd_usb_create_stream+0x3df/0x540 sound/usb/card.c:279
 snd_usb_create_streams sound/usb/card.c:400 [inline]
 usb_audio_probe+0x1319/0x1d60 sound/usb/card.c:967
 usb_probe_interface+0x6ac/0xc00 drivers/usb/core/driver.c:400
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_set_configuration+0x1acf/0x20b0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254
 usb_probe_device+0x1d4/0x380 drivers/usb/core/driver.c:295
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2d8/0x890 drivers/base/dd.c:657
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799
 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459
 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029
 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
 device_add+0x80c/0xbf0 drivers/base/core.c:3692
 usb_new_device+0x9f8/0x15b0 drivers/usb/core/hub.c:2703
 hub_port_connect drivers/usb/core/hub.c:5574 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5714 [inline]
 port_event drivers/usb/core/hub.c:5878 [inline]
 hub_event+0x30c6/0x4700 drivers/usb/core/hub.c:5960
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
 kthread+0x2c6/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/17 07:21 android16-6.12 d9e7ad6b2d4f 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in usb_audio_probe
* Struck through repros no longer work on HEAD.