INFO: task udevd:2860 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D
stack:23720 pid:2860 tgid:2860 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1138/0x47e0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
rwsem_down_read_slowpath+0x5af/0xb40 kernel/locking/rwsem.c:1114
__down_read_common kernel/locking/rwsem.c:1291 [inline]
__down_read kernel/locking/rwsem.c:1304 [inline]
down_read+0xed/0x450 kernel/locking/rwsem.c:1570
kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
d_revalidate fs/namei.c:1030 [inline]
d_revalidate fs/namei.c:1026 [inline]
lookup_fast+0x3c7/0x600 fs/namei.c:1876
walk_component fs/namei.c:2274 [inline]
link_path_walk+0x7d4/0x1cc0 fs/namei.c:2652
path_openat+0x1be/0x31a0 fs/namei.c:4854
do_file_open+0x20e/0x430 fs/namei.c:4887
do_sys_openat2+0x10d/0x1e0 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1cc4095407
RSP: 002b:00007ffe5d1e8e40 EFLAGS: 00000202
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1cc3fa7880 RCX: 00007f1cc4095407
RDX: 0000000000080000 RSI: 00007ffe5d1e8fc0 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000562f411327f5
R13: 0000562f411327f5 R14: 0000000000000001 R15: 0000000000000000
Showing all locks held in the system:
5 locks held by kworker/1:1/28:
1 lock held by khungtaskd/30:
#0:
ffffffff896de960
(
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
1 lock held by udevd/2860:
#0: ffff888100e87980
(
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
2 locks held by getty/2922:
#0:
ffff888112dca0a0
(
&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+0x419/0x14f0 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:3/5225:
4 locks held by kworker/1:5/15700:
1 lock held by syz-executor/16814:
#0:
ffffffff896ea4a8
(
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz-executor/17359:
#0:
ffffffff896ea4a8 (
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by syz-executor/17947:
5 locks held by kworker/1:0/20721:
5 locks held by kworker/0:7/20929:
2 locks held by syz.3.4002/22535:
#0:
ffff888100e87aa0
(
&root->kernfs_supers_rwsem
){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x49/0x120 fs/kernfs/dir.c:1792
#1:
ffff888100e87980 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x51/0x120 fs/kernfs/dir.c:1793
2 locks held by syz.2.4008/22549:
#0: ffff888100e87aa0
(
&root->kernfs_supers_rwsem){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x49/0x120 fs/kernfs/dir.c:1792
#1: ffff888100e87980
(
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x51/0x120 fs/kernfs/dir.c:1793
1 lock held by syz-executor/22551:
#0:
ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
1 lock held by syz-executor/22552:
#0: ffff888100e87980
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
1 lock held by syz-executor/22553:
#0:
ffff888100e87980 (
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
1 lock held by syz-executor/22554:
#0: ffff888100e87980
(
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
=============================================
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 04/18/2026
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:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
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:
yealink 2-1:36.0: unexpected response 0
yealink 2-1:36.0: urb_ctl_callback - urb status -71
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15700 Comm: kworker/1:5 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:mark_usage kernel/locking/lockdep.c:4642 [inline]
RIP: 0010:__lock_acquire+0x6ad/0x2630 kernel/locking/lockdep.c:5191
Code: 0c 00 00 c7 44 24 08 01 00 00 00 e9 50 fe ff ff 85 c0 0f 85 53 0a 00 00 8b b5 2c 0b 00 00 85 f6 0f 84 a5 fd ff ff 89 4c 24 08 04 00 00 00 e9 78 09 00 00 44 8b 84 24 b8 00 00 00 0f b7 4e 22
RSP: 0018:ffffc900001a8498 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffff88810a2f2a20 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff895eaaa0
RBP: ffff88810a2f1dc0 R08: 0000000000000001 R09: 0000000000080000
R10: ffffffff895eaaa0 R11: 0000000000000000 R12: 0000000000000000
R13: 000000000000000e R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8882687a5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f55dc765fc0 CR3: 0000000118f5e000 CR4: 00000000003506f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825
console_lock_spinning_enable+0x72/0x80 kernel/printk/printk.c:1902
console_emit_next_record kernel/printk/printk.c:3177 [inline]
console_flush_one_record+0x739/0xe50 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+0x394/0x3e0 drivers/base/core.c:4930
dev_printk_emit+0xd2/0x10d drivers/base/core.c:4941
__dev_printk+0xcb/0x100 drivers/base/core.c:4953
_dev_err+0xef/0x127 drivers/base/core.c:4996
urb_ctl_callback.cold+0x41/0x8c drivers/input/misc/yealink.c:456
__usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657
usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994
hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2011
handle_softirqs+0x1dd/0x9e0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x160/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 fb 66 68 0b 83 f8 07 0f 87 d9 02 00 00 48 0f a3 05 86 24 61 09 0f 82 a4 02 00 00 8b 35 0e 34 61 09 85 f6 0f 85 bf 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d 66 68 0b 0f 85 ed 02 00 00 48 83 c4
RSP: 0018:ffffc90015e47518 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000004
RDX: 0000000000000000 RSI: ffffffff890a9792 RDI: ffffffff87b08200
RBP: ffff888100e87a10 R08: 00000000d1c3474b R09: 0000000000000082
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
down_write+0x8b/0x1f0 kernel/locking/rwsem.c:1625
kernfs_add_one+0x43d/0x850 fs/kernfs/dir.c:850
__kernfs_create_file+0x295/0x350 fs/kernfs/file.c:1086
sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:313
sysfs_merge_group+0x194/0x340 fs/sysfs/group.c:382
dpm_sysfs_add+0x237/0x280 drivers/base/power/sysfs.c:704
device_add+0x9ef/0x1950 drivers/base/core.c:3651
usb_create_ep_devs+0x160/0x2b0 drivers/usb/core/endpoint.c:162
usb_new_device.cold+0xcf3/0x115c drivers/usb/core/hub.c:2725
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
process_scheduled_works kernel/workqueue.c:3397 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
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