INFO: task kworker/0:4:5228 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4 state:D stack:21928 pid:5228 tgid:5228 ppid:2 task_flags:0x4288060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x12fc/0x3b90 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
rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2142
unregister_netdev+0x15/0x60 net/core/dev.c:12246
usbnet_disconnect+0x109/0x500 drivers/net/usb/usbnet.c:1658
usb_unbind_interface+0x1da/0x9e0 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:571 [inline]
device_remove+0x122/0x170 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+0x1aa2/0x5060 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+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x700 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/30:
#0: ffffffff892c76e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff892c76e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff892c76e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by dhcpcd/2890:
2 locks held by getty/2915:
#0: ffff888100ec20a0 (&tty->ldisc_sem){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1:
ffffc900000432f0
(&ldata->atomic_read_lock){+.+.}-{4:4}
, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
6 locks held by kworker/0:3/5215:
#0: ffff8881066f7d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000226fd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810bb07198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#2: ffff88810bb07198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898
#3: ffff88810d7c7198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#3: ffff88810d7c7198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4: ffff88812e24a160 (
&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5: ffffffff8a5fc208 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
#5: ffffffff8a5fc208 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11319
7 locks held by kworker/1:3/5218:
#0: ffff8881f59388d8
(
&rq->__lock
){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:636 [inline]
){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1519 [inline]
){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1841 [inline]
){-.-.}-{2:2}, at: __schedule+0x2ec/0x3b90 kernel/sched/core.c:6865
#1:
ffffc9000228fd10 ((work_completion)(&(&d->rc_query_work)->work)#2){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff8881f59258d8
(&base->lock
){-.-.}-{2:2}, at: console_trylock_spinning kernel/printk/printk.c:2061 [inline]
){-.-.}-{2:2}, at: vprintk_emit+0x57e/0x6d0 kernel/printk/printk.c:2449
#3: ffff8881f59388d8 (&rq->__lock
){-.-.}-{2:2}
, at: debug_object_activate+0x14c/0x4c0 lib/debugobjects.c:818
#4: ffff8881f5937818
(&pool->lock
){-.-.}-{2:2}
, at: __queue_work+0x26b/0x1160 kernel/workqueue.c:2299
#5: ffff88811d8660e0
(&p->pi_lock
){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
){-.-.}-{2:2}, at: try_to_wake_up+0xb9/0x1480 kernel/sched/core.c:4216
#6:
ffff8881f59388d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:636 [inline]
ffff8881f59388d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1519 [inline]
ffff8881f59388d8 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1841 [inline]
ffff8881f59388d8 (&rq->__lock){-.-.}-{2:2}, at: ttwu_queue kernel/sched/core.c:4002 [inline]
ffff8881f59388d8 (&rq->__lock){-.-.}-{2:2}, at: try_to_wake_up+0x679/0x1480 kernel/sched/core.c:4328
4 locks held by udevd/5221:
#0: ffff888136f2d540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1: ffff888120e8a088 (
&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff88811e195b48 (kn->active#9){++++}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88813831b198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline]
#3: ffff88813831b198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
6 locks held by kworker/0:4/5228:
#0: ffff8881066f7d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc9000222fd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810b307198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#2: ffff88810b307198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898
#3: ffff888119054198 (
&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9c0 drivers/usb/core/hub.c:2335
#4: ffff88810770a160 (&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: ffffffff8a5fc208 (rtnl_mutex
){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2142
3 locks held by kworker/0:5/5264:
#0: ffff888100080d48
((wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900023afd10 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810aff1198
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
(&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline]
(&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b1/0x620 drivers/net/wireless/ath/ath9k/hif_usb.c:1294
6 locks held by kworker/0:6/5267:
#0: ffff8881066f7d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900023cfd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810b761198 (&dev->mutex
){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
){....}-{4:4}, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898
#3: ffff888117232198
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
(&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4: ffff88813a875160
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
(&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5: ffffffff8a5fc208
(rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
, at: register_netdev+0x18/0x50 net/core/dev.c:11319
6 locks held by kworker/1:7/5739:
#0: ffff8881066f7d48
((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900122e7d10 ((work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810aff1198
(&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898
#3: ffff88811a318198
(
&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4: ffff88810db30160
(&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
(&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5:
ffffffff8a5fc208 (
rtnl_mutex){+.+.}-{4:4}
, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
, at: register_netdev+0x18/0x50 net/core/dev.c:11319
4 locks held by udevd/6051:
#0:
ffff8881202ece80
(&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1:
ffff888109b46488 (
&of->mutex#2){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2:
ffff88810373c878
(
kn->active#9){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
kn->active#9){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88810d7c7198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline]
#3: ffff88810d7c7198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/6055:
#0: ffff88810f2a30a0
(&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1: ffff888120eb5c88
(&of->mutex#2){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff888132b631e8 (
kn->active#9){++++}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88811a318198
(&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline]
(&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
6 locks held by kworker/1:8/7944:
#0: ffff8881066f7d48
((wq_completion)usb_hub_wq
){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900159a7d10 ((work_completion)(&hub->events)){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810b305198 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898
#3: ffff88813831b198 (&dev->mutex){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4: ffff88812b582160 (
&dev->mutex){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5: ffffffff8a5fc208
(rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
(rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11319
3 locks held by kworker/u8:0/8129:
#0: ffff888111a0d948 ((wq_completion)ipv6_addrconf
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc900152efd10 (
(work_completion)(&(&net->ipv6.addr_chk_work)->work)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffffffff8a5fc208 (rtnl_mutex){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x700 arch/x86/kernel/process.c:148
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: 2890 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:401
Code: 18 a4 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 eb 66 04 e8 d8 49 02 ff eb a2 e8 61 4a
RSP: 0018:ffffc900014c6f08 EFLAGS: 00000006
RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: ffffffff82d9e2a0 RDI: ffffffff93b871e0
RBP: ffffffff93b871a0 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff93b871f0 R14: ffffffff93b871a0 R15: ffffffff93b87460
FS: 00007f85b0547740(0000) GS:ffff888268ff4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd41c67020 CR3: 0000000116cba000 CR4: 00000000003506f0
Call Trace:
serial_port_in include/linux/serial_core.h:793 [inline]
serial8250_console_write+0x249/0x1890 drivers/tty/serial/8250/8250_port.c:3360
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x801/0xc60 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
__netdev_printk+0x1fb/0x500 net/core/dev.c:12598
netdev_warn+0xe4/0x120 net/core/dev.c:12651
asix_write_cmd+0xf1/0x100 drivers/net/usb/asix_common.c:57
asix_set_sw_mii drivers/net/usb/asix_common.c:75 [inline]
asix_check_host_enable+0x154/0x240 drivers/net/usb/asix_common.c:98
__asix_mdio_read+0x9c/0x260 drivers/net/usb/asix_common.c:484
asix_phy_reset+0x106/0x1f0 drivers/net/usb/asix_devices.c:215
ax88178_reset+0x42d/0x12f0 drivers/net/usb/asix_devices.c:1125
usbnet_open+0xcc/0xbe0 drivers/net/usb/usbnet.c:910
__dev_open+0x3a0/0x850 net/core/dev.c:1682
__dev_change_flags+0x55d/0x720 net/core/dev.c:9549
netif_change_flags+0x8d/0x160 net/core/dev.c:9612
dev_change_flags+0xb6/0x170 net/core/dev_api.c:68
devinet_ioctl+0x11d5/0x1f50 net/ipv4/devinet.c:1199
inet_ioctl+0x3a7/0x3f0 net/ipv4/af_inet.c:1001
sock_do_ioctl+0x115/0x280 net/socket.c:1238
sock_ioctl+0x42f/0x6a0 net/socket.c:1359
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl fs/ioctl.c:584 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f85b0647378
Code: 00 00 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 07 89 d0 c3 0f 1f 40 00 48 8b 15 49 3a 0d
RSP: 002b:00007ffcf87a4f18 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f85b0647378
RDX: 00007ffcf87b5110 RSI: 0000000000008914 RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcf87c52b0
R13: 00007f85b05476c8 R14: 0000000000000028 R15: 0000000000008914