INFO: task kworker/1:1:37 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1 state:D stack:20936 pid:37 tgid:37 ppid:2 task_flags:0x4288060 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
rwsem_down_write_slowpath+0x4c2/0x12b0 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1c7/0x1f0 kernel/locking/rwsem.c:1632
usb_deregister_dev+0x7c/0x210 drivers/usb/core/file.c:186
chaoskey_disconnect+0xa9/0x300 drivers/usb/misc/chaoskey.c:235
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
bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
device_del+0x376/0x9b0 drivers/base/core.c:3961
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/0:5:5233 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:5 state:D
stack:20488 pid:5233 tgid:5233 ppid:2 task_flags:0x4288060 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
rwsem_down_write_slowpath+0x4c2/0x12b0 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1c7/0x1f0 kernel/locking/rwsem.c:1632
usb_deregister_dev+0x7c/0x210 drivers/usb/core/file.c:186
sisusb_disconnect+0x5e/0x200 drivers/usb/misc/sisusbvga/sisusbvga.c:2921
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
bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
device_del+0x376/0x9b0 drivers/base/core.c:3961
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
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#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
6 locks held by kworker/1:1/37:
#0: ffff88810568ed40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90000277d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88810b7b61d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88810b7b61d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3: ffff888107aa51d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff888107aa51d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2341
#4: ffff888134d371a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff888134d371a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#4: ffff888134d371a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
#5: ffffffff8a338e68 (minor_rwsem){++++}-{4:4}, at: usb_deregister_dev+0x7c/0x210 drivers/usb/core/file.c:186
6 locks held by kworker/0:2/119:
#0:
ffff88810568ed40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90001567d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88810ab461d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88810ab461d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3:
ffff888114e4b1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
ffff888114e4b1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#4: ffff8881395f11a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff8881395f11a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#5: ffffffff8a338e68 (minor_rwsem){++++}-{4:4}, at: usb_register_dev+0x11d/0x570 drivers/usb/core/file.c:134
2 locks held by getty/2919:
#0: ffff8881151b10a0 (&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
6 locks held by kworker/0:5/5233:
#0: ffff88810568ed40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc9000352fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffff88810abc61d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
ffff88810abc61d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3: ffff8881331dc1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff8881331dc1d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2341
#4: ffff888134d331a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff888134d331a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
#4: ffff888134d331a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
#5:
ffffffff8a338e68 (minor_rwsem){++++}-{4:4}, at: usb_deregister_dev+0x7c/0x210 drivers/usb/core/file.c:186
2 locks held by kworker/1:2/5234:
4 locks held by udevd/5275:
#0: ffff888109349878 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff8881235d4080 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:165
#2:
ffff8881141a1c38 (kn->active#23){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
ffff8881141a1c38 (kn->active#23){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:166
#3: ffff888114e4b1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1107 [inline]
#3: ffff888114e4b1d8 (&dev->mutex){....}-{4:4}, at: product_show+0x26/0xa0 drivers/usb/core/sysfs.c:141
2 locks held by kworker/1:5/5311:
#0: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:667 [inline]
#0: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1653 [inline]
#0: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1991 [inline]
#0: ffff8881f57397a0 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2dc/0x47d0 kernel/sched/core.c:7108
#1: ffffc90003e4fd18
((work_completion)(&(&d->rc_query_work)->work)
){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
2 locks held by kworker/0:7/6352:
#0:
ffff8881f56397a0
(
&rq->__lock
){-.-.}-{2:2}
, at: raw_spin_rq_lock_nested+0x20/0x30 kernel/sched/core.c:667
#1: ffffc900131b7d18 (
(work_completion)(&(&d->rc_query_work)->work)
){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
3 locks held by kworker/1:6/9156:
#0:
ffff88810006b140
(
(wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc900134a7d18 (
free_ipc_work
){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffffffff896ee5e8 (rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
5 locks held by kworker/u8:3/10504:
#0:
ffff888100e98940
((wq_completion)netns){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc90014b07d18
(
net_cleanup_work
){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffffffff8ab0c1c8 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673
#3:
ffffffff8ab24c00
(
rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
#4:
ffffffff896ee5e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
6 locks held by kworker/0:1/12401:
#0: ffff88810568ed40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc900131a7d18
((work_completion)(&hub->events)){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffff88810af461d8
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3:
ffff888114d331d8
(&dev->mutex){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#4:
ffff88813ba3a1a0 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#5: ffffffff8a338e68 (
minor_rwsem){++++}-{4:4}
, at: usb_register_dev+0x11d/0x570 drivers/usb/core/file.c:134
6 locks held by kworker/0:4/12544:
#0:
ffff88810568ed40
(
(wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc90012dc7d18
((work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffff88810bb0e1d8
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
(&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3: ffff8881203e11d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff8881203e11d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#4: ffff8881236171a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff8881236171a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#5:
ffffffff8a338e68
(
minor_rwsem
){++++}-{4:4}
, at: usb_register_dev+0x11d/0x570 drivers/usb/core/file.c:134
7 locks held by kworker/1:8/12721:
2 locks held by syz.5.2805/14197:
#0:
ffffffff8a338e68 (minor_rwsem){++++}-{4:4}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
#1: ffff888114b388c8 (&(sisusb->lock)){+.+.}-{4:4}, at: sisusb_open+0xb6/0x4b0 drivers/usb/misc/sisusbvga/sisusbvga.c:2213
6 locks held by kworker/1:9/14196:
#0:
ffff88810568ed40
(
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc900146d7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2: ffff88810b70e1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff88810b70e1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5904
#3: ffff888139f371d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff888139f371d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#4: ffff88812864c1a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff88812864c1a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073
#5:
ffffffff8a338e68
(minor_rwsem){++++}-{4:4}, at: usb_register_dev+0x11d/0x570 drivers/usb/core/file.c:134
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 29 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: 12721 Comm: kworker/1:8 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:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:402
Code: 82 88 fe 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 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 cd 85 53 04 e8 38 e8 f0 fe eb a2 e8 c1 e8
RSP: 0018:ffffc900135176f0 EFLAGS: 00000006
RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: ffffffff832b8160 RDI: ffffffff94249da0
RBP: ffffffff94249d60 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff94249db0 R14: ffffffff9408a8a0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888268736000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffea2bccf6c CR3: 0000000116a42000 CR4: 00000000003506f0
Call Trace:
serial_port_in include/linux/serial_core.h:808 [inline]
serial8250_console_write+0x23c/0x1a50 drivers/tty/serial/8250/8250_port.c:3349
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
legacy_dvb_usb_read_remote_control.cold+0x11/0x16 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124
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