INFO: task kworker/1:7:5909 blocked for more than 141 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:7 state:D
stack:21944 pid:5909 tgid:5909 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
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
uevent_net_broadcast_untagged lib/kobject_uevent.c:317 [inline]
kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline]
kobject_uevent_env+0xba8/0x18b0 lib/kobject_uevent.c:611
device_add+0x1173/0x1970 drivers/base/core.c:3738
usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2698
hub_port_connect drivers/usb/core/hub.c:5570 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5710 [inline]
port_event drivers/usb/core/hub.c:5874 [inline]
hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5956
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
</TASK>
INFO: task syz.1.1053:8969 blocked for more than 142 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1053 state:R
stack:28936 pid:8969 tgid:8968 ppid:2970 task_flags:0x400040 flags:0x00080002
Call Trace:
<TASK>
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
</TASK>
Showing all locks held in the system:
6 locks held by kworker/0:0/9:
1 lock held by kworker/R-mm_pe/13:
1 lock held by khungtaskd/29:
#0:
ffffffff896e2b40
(
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
6 locks held by kworker/0:2/126:
1 lock held by udevd/2857:
#0:
ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1217
2 locks held by getty/2919:
#0:
ffff8881127f50a0 (&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
4 locks held by udevd/5193:
#0:
ffff888105f793f8 (&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1:
ffff888124105880
(&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:165
#2:
ffff8881259233c8 (kn->active#9
){.+.+}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:166
#3:
ffff88813bad91d8
(
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:1107 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
6 locks held by kworker/0:3/5227:
#0:
ffff8881056c2940
(
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1: ffffc90002dcfd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffff88810afbd1d8
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5902
#3:
ffff8881056de1d8
(
&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:
ffff88813b8171a0
(
&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:
ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_activate fs/kernfs/dir.c:1462 [inline]
ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_add_one+0x5dd/0xaa0 fs/kernfs/dir.c:868
2 locks held by kworker/0:4/5239:
4 locks held by udevd/5242:
#0: ffff888124048ab8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1:
ffff88811498f880
(
&of->mutex
#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:165
#2:
ffff888115666b48
(
kn->active
#9
){.+.+}-{0:0}
, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:166
#3: ffff88813b8101d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1107 [inline]
#3: ffff88813b8101d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
4 locks held by udevd/5438:
#0: ffff888107b11bd8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff88811981c080 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:165
#2: ffff8881359eeb48 (kn->active#9){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
#2: ffff8881359eeb48 (kn->active#9){.+.+}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:166
#3:
ffff8881056de1d8 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1107 [inline]
ffff8881056de1d8 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
5 locks held by kworker/0:7/5619:
4 locks held by kworker/1:7/5909:
#0:
ffff8881056c2940
(
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc9001302fd18
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffff88810bb0d1d8
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:1102 [inline]
, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5902
#3:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}, at: kernfs_add_one+0x38/0xaa0 fs/kernfs/dir.c:825
3 locks held by kworker/0:5/8588:
2 locks held by kworker/0:6/8970:
2 locks held by syz.4.1054/8972:
#0:
ffff888100e87aa0 (&root->kernfs_supers_rwsem){++++}-{4:4}, at: kernfs_remove fs/kernfs/dir.c:1622 [inline]
ffff888100e87aa0 (&root->kernfs_supers_rwsem){++++}-{4:4}, at: kernfs_remove+0x3b/0x70 fs/kernfs/dir.c:1613
#1: ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_remove fs/kernfs/dir.c:1623 [inline]
#1: ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_remove+0x43/0x70 fs/kernfs/dir.c:1613
1 lock held by syz.0.1055/8977:
#0: ffffffff896ee5e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.3.1056/8979:
#0:
ffffffff896ee5e8
(
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
2 locks held by syz-executor/8984:
#0:
ffffffff8ab0a5c8 (pernet_ops_rwsem){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8ab23000
(
rtnl_mutex
){+.+.}-{4:4}
, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/8987:
#0:
ffffffff8ab0a5c8
(
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8ab23000
(
rtnl_mutex
){+.+.}-{4:4}
, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/9001:
#0:
ffffffff8ab0a5c8
(
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8ab23000
(
rtnl_mutex
){+.+.}-{4:4}
, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/9004:
#0:
ffffffff8ab0a5c8
(
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8ab23000
(
rtnl_mutex
){+.+.}-{4:4}
, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
4 locks held by kworker/u8:7/9009:
#0:
ffff888100e98940
(
(wq_completion)netns
){+.+.}-{0:0}
, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297
#1:
ffffc900131dfd18
(
net_cleanup_work
){+.+.}-{0:0}
, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298
#2:
ffffffff8ab0a5c8
(
pernet_ops_rwsem
){++++}-{4:4}
, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673
#3:
ffffffff8ab23000
(
rtnl_mutex
){+.+.}-{4:4}
, at: cfg80211_pernet_exit+0x17/0x120 net/wireless/core.c:1863
3 locks held by syz-executor/9010:
#0:
ffffffff8ab0a5c8
(
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8ab23000
(
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
, at: register_netdev+0x18/0x50 net/core/dev.c:11553
#2:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_add_one+0x38/0xaa0 fs/kernfs/dir.c:825
1 lock held by syz-executor/9056:
#0:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1217
1 lock held by syz-executor/9057:
#0:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1217
1 lock held by syz-executor/9058:
#0:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1217
1 lock held by syz-executor/9059:
#0:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1217
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
Call Trace:
<TASK>
__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
</TASK>
Sending NMI from CPU 1 to CPUs 0:
yealink 3-1:36.0: urb_ctl_callback - urb status -71
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8588 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:402
Code: 95 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 c3 cc cc cc cc e8 e8 f5 f0 fe eb a2 e8 71 f6
RSP: 0018:ffffc90000007460 EFLAGS: 00000002
RAX: dffffc0000000060 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff832b5ad0 RDI: ffffffff94245da0
RBP: ffffffff94245d60 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff2848c06 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff88826863a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f854b5cad0c CR3: 00000000094ac000 CR4: 00000000003506f0
Call Trace:
<IRQ>
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:1982
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
dev_vprintk_emit+0x391/0x3e0 drivers/base/core.c:4996
dev_printk_emit+0xd2/0x10d drivers/base/core.c:5007
__dev_printk+0xcb/0x100 drivers/base/core.c:5019
_dev_err+0xef/0x127 drivers/base/core.c:5062