INFO: task kworker/0:2:120 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2 state:D stack:20160 pid:120 tgid:120 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1325/0x47d0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821
device_lock include/linux/device.h:1102 [inline]
device_del+0xa0/0x9b0 drivers/base/core.c:3923
usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2350
hub_port_connect drivers/usb/core/hub.c:5412 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5712 [inline]
port_event drivers/usb/core/hub.c:5876 [inline]
hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5958
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task kworker/1:3:5218 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:3 state:D stack:21040 pid:5218 tgid:5218 ppid:2 task_flags:0x4288060 flags:0x00080000
Workqueue: events request_firmware_work_func
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1325/0x47d0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
lbs_wait_for_firmware_load+0x11e/0x1e0 drivers/net/wireless/marvell/libertas/firmware.c:117
lbs_remove_card+0x84/0x390 drivers/net/wireless/marvell/libertas/main.c:913
if_usb_disconnect+0xc5/0x270 drivers/net/wireless/marvell/libertas/if_usb.c:317
usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:461
device_remove drivers/base/dd.c:618 [inline]
device_remove+0x12a/0x180 drivers/base/dd.c:610
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
usb_driver_release_interface drivers/usb/core/driver.c:643 [inline]
usb_forced_unbind_intf+0x1a4/0x240 drivers/usb/core/driver.c:1137
usb_reset_device+0x411/0xaa0 drivers/usb/core/hub.c:6409
if_usb_reset_device.isra.0+0x21e/0x290 drivers/net/wireless/marvell/libertas/if_usb.c:400
if_usb_prog_firmware.cold+0x161/0x192 drivers/net/wireless/marvell/libertas/if_usb.c:918
lbs_fw_loaded drivers/net/wireless/marvell/libertas/firmware.c:23 [inline]
helper_firmware_cb drivers/net/wireless/marvell/libertas/firmware.c:80 [inline]
helper_firmware_cb+0x1f7/0x2d0 drivers/net/wireless/marvell/libertas/firmware.c:64
request_firmware_work_func+0x13f/0x440 drivers/base/firmware_loader/main.c:1164
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 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:
no locks held by ksoftirqd/1/22.
1 lock held by khungtaskd/30:
#0: ffffffff896e2b40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff896e2b40 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff896e2b40 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
5 locks held by kworker/0:2/120:
#0: ffff888105adb940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900015b7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88810b3841d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88810b3841d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3: ffff88813abfb1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff88813abfb1d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2341
#4:
ffff88813ad831a0 (
&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
&dev->mutex){....}-{4:4}, at: device_del+0xa0/0x9b0 drivers/base/core.c:3923
2 locks held by getty/2917:
#0: ffff888114dd30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900000452e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:3/5218:
#0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000387fd18 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88813ad831a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88813ad831a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#2: ffff88813ad831a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
4 locks held by udevd/5228:
#0: ffff88810d3e6998 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff888136414080 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:165
#2: ffff8881165fb2d8 (kn->active#21){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff8881165fb2d8 (kn->active#21){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:166
#3: ffff88811f70f1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1107 [inline]
#3: ffff88811f70f1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
7 locks held by kworker/1:6/5375:
#0: ffff888105adb940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900041a7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88810ab7c1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88810ab7c1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3: ffff88811f70f1d8
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
(&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#4:
ffff88811e8241a0
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
(&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#5: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:667 [inline]
#5: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1653 [inline]
#5: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1991 [inline]
#5: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2dc/0x47d0 kernel/sched/core.c:7108
#6: ffffffff941593b8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x144/0x4b0 lib/debugobjects.c:873
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
__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:122
nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1123 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:delay_tsc+0x37/0xc0 arch/x86/lib/delay.c:79
Code: 00 41 54 55 53 e8 a9 7b 08 fa e8 94 48 01 00 41 89 c4 0f 01 f9 66 90 48 c1 e2 20 48 09 c2 48 89 d5 eb 16 f3 90 bf 01 00 00 00 84 7b 08 fa e8 6f 48 01 00 44 39 e0 75 36 0f 01 f9 66 90 48 c1
RSP: 0018:ffffc90003b6f638 EFLAGS: 00000002
RAX: 0000000000000003 RBX: 000000a9e4e053c0 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff87b15400 RDI: 0000000000000001
RBP: 000000a9e4e0524a R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000806 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000899 R14: fffffbfff2849406 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888268736000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe107b8c10 CR3: 000000012330c000 CR4: 00000000003506f0
Call Trace:
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0xf3/0x210 drivers/tty/serial/8250/8250_port.c:1988
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3235 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3300 [inline]
serial8250_console_write+0xdfd/0x1a50 drivers/tty/serial/8250/8250_port.c:3385
console_emit_next_record kernel/printk/printk.c:3183 [inline]
console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269
console_flush_all kernel/printk/printk.c:3343 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0x103/0x260 kernel/printk/printk.c:3413
vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
_printk+0xcf/0x110 kernel/printk/printk.c:2504
m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline]
m920x_rc_query.cold+0x2b/0x30 drivers/media/usb/dvb-usb/m920x.c:188
legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245