INFO: task kworker/1:3:5624 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/1:3 state:D stack:20248 pid:5624 tgid:5624 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
snd_card_free+0x147/0x1d0 sound/core/init.c:661
usb_audio_probe+0x1e23/0x2380 sound/usb/card.c:1082
usb_probe_interface+0x659/0xc70 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:709
__driver_probe_device+0x1ef/0x380 drivers/base/dd.c:871
driver_probe_device+0x4f/0x240 drivers/base/dd.c:901
__device_attach_driver+0x279/0x430 drivers/base/dd.c:1029
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1101
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1156
bus_probe_device+0x12a/0x220 drivers/base/bus.c:613
device_add+0x7e9/0xbb0 drivers/base/core.c:3706
usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
usb_probe_device+0x1c4/0x3b0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:709
__driver_probe_device+0x1ef/0x380 drivers/base/dd.c:871
driver_probe_device+0x4f/0x240 drivers/base/dd.c:901
__device_attach_driver+0x279/0x430 drivers/base/dd.c:1029
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1101
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1156
bus_probe_device+0x12a/0x220 drivers/base/bus.c:613
device_add+0x7e9/0xbb0 drivers/base/core.c:3706
usb_new_device+0xa08/0x16f0 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+0x2a1c/0x4f30 drivers/usb/core/hub.c:5953
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:9/3340:
2 locks held by getty/5381:
#0: ffff88803202d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
6 locks held by kworker/1:3/5624:
#0: ffff888021ecd540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff888021ecd540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc900042d7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc900042d7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffff88802b0ae1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802b0ae1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff88805ce241d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff88805ce241d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#4: ffff88805b7e21a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff88805b7e21a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#5: ffffffff8fd35c80 (register_mutex#6){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#5: ffffffff8fd35c80 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x63a/0x2380 sound/usb/card.c:952
6 locks held by kworker/0:6/5717:
#0: ffff888021ecd540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff888021ecd540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc900047d7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc900047d7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffff88802aff71d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802aff71d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff88805816f1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff88805816f1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#4: ffff88805816e1a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff88805816e1a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#5: ffffffff8fd35c80 (register_mutex#6){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#5: ffffffff8fd35c80 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x63a/0x2380 sound/usb/card.c:952
6 locks held by kworker/1:0/32172:
#0: ffff888021ecd540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff888021ecd540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc90003c8fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc90003c8fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffff88802b0341d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88802b0341d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff88802acca1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff88802acca1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#4: ffff88804e43b1a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff88804e43b1a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1076
#5: ffffffff8fd35c80 (register_mutex#6){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#5: ffffffff8fd35c80 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x63a/0x2380 sound/usb/card.c:952
4 locks held by udevd/565:
#0: ffff888059fddab8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183
#1: ffff88807f850480 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff88805e94a968 (kn->active#31){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88805e94a968 (kn->active#31){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff88805816f1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
#3: ffff88805816f1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/566:
#0: ffff8880784fc2d8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183
#1: ffff88805bf86080 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff88805ee05b48 (kn->active#31){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88805ee05b48 (kn->active#31){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff88802acca1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1045 [inline]
#3: ffff88802acca1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3340 Comm: kworker/u8:9 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3801 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline]
RIP: 0010:__lock_acquire+0xc59/0x2cf0 kernel/locking/lockdep.c:5237
Code: 00 00 00 48 c7 c7 90 b1 82 8e 4c 89 fe e8 af 4d 4d 03 48 8b 54 24 18 eb c3 48 8b 48 18 48 39 e9 0f 84 b9 00 00 00 48 8b 40 08 <48> 85 c0 0f 84 ca fe ff ff 48 83 c0 f8 75 e0 e9 bf fe ff ff 48 8b
RSP: 0018:ffffc9000db3f310 EFLAGS: 00000007
RAX: ffffffff94424378 RBX: 0000000000021248 RCX: 64dee99db5e0cf99
RDX: 00000000693fed00 RSI: 0000000001a2ef72 RDI: ffff888032720000
RBP: f1ba2f2e6bdadc43 R08: ffffffff81b2cf25 R09: ffffffff9a48a588
R10: dffffc0000000000 R11: ffffed1003f627b1 R12: ffff888032720c80
R13: ffff888032720c80 R14: ffff888032720000 R15: 0000000000000006
FS: 0000000000000000(0000) GS:ffff888125290000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556fc5ee2c30 CR3: 000000007bf82000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73
ktime_get+0x45/0x220 kernel/time/timekeeping.c:965
hrtick_schedule_exit kernel/sched/core.c:985 [inline]
finish_lock_switch kernel/sched/core.c:5123 [inline]
finish_task_switch+0x312/0xbe0 kernel/sched/core.c:5242
context_switch kernel/sched/core.c:5390 [inline]
__schedule+0x17bc/0x5680 kernel/sched/core.c:7188
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
on_each_cpu_cond_mask+0x7a/0x80 kernel/smp.c:1058
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:913
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245