INFO: task kworker/1:5:6133 blocked for more than 147 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D
stack:23480 pid:6133 tgid:6133 ppid:2 task_flags:0x4288060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
class_mutex_constructor include/linux/mutex.h:228 [inline]
__input_unregister_device+0x184/0x4d0 drivers/input/input.c:2221
input_unregister_device+0xb9/0x100 drivers/input/input.c:2452
imon_disconnect+0x218/0x650 drivers/media/rc/imon.c:2524
usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:571 [inline]
device_remove+0x125/0x170 drivers/base/dd.c:563
__device_release_driver drivers/base/dd.c:1274 [inline]
device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1297
bus_remove_device+0x22f/0x420 drivers/base/bus.c:579
device_del+0x396/0x9f0 drivers/base/core.c:3878
usb_disable_device+0x355/0x7d0 drivers/usb/core/message.c:1418
usb_disconnect+0x2e1/0x9c0 drivers/usb/core/hub.c:2344
hub_port_connect drivers/usb/core/hub.c:5406 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x1c81/0x4fe0 drivers/usb/core/hub.c:5952
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
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/31:
#0:
ffffffff8e5c1220
(
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
7 locks held by kworker/0:2/55:
2 locks held by kworker/u8:5/178:
#0:
ffff88801b881148
(
(wq_completion)events_unbound
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc90002ff7d10
(
connector_reaper_work
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u8:7/3503:
#0:
ffff88801b881148
(
(wq_completion)events_unbound
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc9000cf37d10
(
(reaper_work).work
){+.+.}-{0:0}
, at: psi_sched_switch kernel/sched/stats.h:220 [inline]
, at: __schedule+0x1861/0x5de0 kernel/sched/core.c:6955
2 locks held by getty/5599:
#0:
ffff888035f360a0
(
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0
(
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
5 locks held by kworker/0:3/5853:
6 locks held by kworker/0:4/5884:
6 locks held by kworker/1:5/6133:
#0:
ffff8881442f1948
(
(wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc90004d6fd10
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2:
ffff8880296e1198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898
#3:
ffff888033a04198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: usb_disconnect+0x10a/0x9c0 drivers/usb/core/hub.c:2335
#4:
ffff888022fff160
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_driver_lock drivers/base/dd.c:1096 [inline]
, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1294
#5:
ffffffff8fb97bc8
(input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:228 [inline]
(input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2221
7 locks held by kworker/0:6/6208:
#0:
ffff8881442f1948
(
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc90004f2fd10
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2:
ffff888145b31198
(
&dev->mutex
){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
){....}-{4:4}, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898
#3:
ffff8880337e2198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: usb_disconnect+0x10a/0x9c0 drivers/usb/core/hub.c:2335
#4:
ffff88807a7df160
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_driver_lock drivers/base/dd.c:1096 [inline]
, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1294
#5:
ffffffff8fb97bc8
(
input_mutex
){+.+.}-{4:4}
, at: class_mutex_constructor include/linux/mutex.h:228 [inline]
, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2221
#6:
ffffffff8e5cc7b8
(rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
7 locks held by kworker/0:7/6209:
#0:
ffff8881442f1948
(
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc90004f3fd10
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2:
ffff888145b19198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898
#3:
ffff888076a57198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4:
ffff888030c7c160
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5:
ffff888078bbd088
(
&ictx->lock
){+.+.}-{4:4}
, at: imon_init_intf0 drivers/media/rc/imon.c:2233 [inline]
, at: imon_probe+0x9e2/0x3ac0 drivers/media/rc/imon.c:2434
#6:
ffffffff8fb97bc8
(
input_mutex
){+.+.}-{4:4}
, at: class_mutex_constructor include/linux/mutex.h:228 [inline]
, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2221
4 locks held by udevd/6289:
#0: ffff88802238dd58 (&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1:
ffff888032dbd888
(
&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2:
ffff88807df89008
(
kn->active
#25
){.+.+}-{0:0}
, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3:
ffff888033a04198
(
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:916 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/6292:
#0:
ffff88807327a0a0
(
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1:
ffff888023289088
(
&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2:
ffff888074bac4b8
(kn->active#25){.+.+}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3: ffff888076a57198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline]
#3: ffff888076a57198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/6294:
#0: ffff88807b44be80 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1: ffff888076749088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2:
ffff8880327b71e8
(
kn->active#27){.+.+}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3: ffff8880337e2198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline]
#3: ffff8880337e2198 (&dev->mutex){....}-{4:4}, at: product_show+0x26/0xa0 drivers/usb/core/sysfs.c:141
4 locks held by kworker/0:10/6327:
4 locks held by udevd/6346:
#0:
ffff88802238d1c8
(
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1:
ffff88807601f088
(&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2:
ffff88807c2314b8
(
kn->active
#25
){.+.+}-{0:0}
, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3:
ffff88807d7b3198
(
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:916 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
2 locks held by dhcpcd/6931:
#0:
ffff88803597a258
(
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1667 [inline]
, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3251
#1: ffffffff8e5cc7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by dhcpcd/6932:
#0:
ffff888031566258
(
sk_lock-AF_PACKET
){+.+.}-{0:0}
, at: lock_sock include/net/sock.h:1667 [inline]
, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3251
1 lock held by dhcpcd/6933:
#0:
ffff888074784258
(
sk_lock-AF_PACKET
){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline]
){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3251
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:407
Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 21 aa bd fc eb a0 e8 aa aa bd
RSP: 0018:ffffc90000147340 EFLAGS: 00000002
RAX: 0000000000000039 RBX: 00000000000003f8 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: ffffffff85643ac5 RDI: ffffffff9b1110a0
RBP: ffffffff9b111060 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000039 R14: ffffffff9b111060 R15: ffffffff85643a60
FS: 0000000000000000(0000) GS:ffff8881246b9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005646225ae100 CR3: 000000007b45d000 CR4: 00000000003526f0
Call Trace:
serial_port_out include/linux/serial_core.h:798 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3246 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3318 [inline]
serial8250_console_write+0xfbd/0x1890 drivers/tty/serial/8250/8250_port.c:3396
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x7fe/0xc60 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
dev_vprintk_emit drivers/base/core.c:4914 [inline]
dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925
__dev_printk+0xf5/0x270 drivers/base/core.c:4937
_dev_warn+0xe4/0x120 drivers/base/core.c:4981
usb_rx_callback_intf0+0x11c/0x1a0 drivers/media/rc/imon.c:1768
__usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661
usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745
dummy_timer+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
run_ksoftirqd kernel/softirq.c:968 [inline]
run_ksoftirqd+0x3a/0x60 kernel/softirq.c:960
smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245