INFO: task udevd:2851 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:24568 pid:2851 tgid:2851 ppid:1 task_flags:0x400140 flags:0x00004002
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
rwsem_down_read_slowpath+0x64e/0xbf0 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1261 [inline]
__down_read kernel/locking/rwsem.c:1274 [inline]
down_read+0xef/0x480 kernel/locking/rwsem.c:1539
kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
d_revalidate fs/namei.c:929 [inline]
d_revalidate fs/namei.c:925 [inline]
lookup_fast+0x266/0x610 fs/namei.c:1769
walk_component+0x5b/0x5b0 fs/namei.c:2125
link_path_walk+0x627/0xe20 fs/namei.c:2497
path_lookupat+0x15a/0x6d0 fs/namei.c:2653
filename_lookup+0x224/0x5f0 fs/namei.c:2683
do_readlinkat+0xce/0x3a0 fs/stat.c:576
__do_sys_readlink fs/stat.c:613 [inline]
__se_sys_readlink fs/stat.c:610 [inline]
__x64_sys_readlink+0x78/0xc0 fs/stat.c:610
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: 0033:0x7f32681273a7
RSP: 002b:00007fff9881fd58 EFLAGS: 00000246
ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007fff98820230 RCX: 00007f32681273a7
RDX: 0000000000000400 RSI: 00007fff9881fd60 RDI: 00007fff98820230
RBP: 00007fff9881fd60 R08: 0000000000000075 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 000055c45162f100 R14: 0000000000000001 R15: 00007fff98821b30
Showing all locks held in the system:
6 locks held by kworker/1:0/23:
1 lock held by khungtaskd/30:
#0:
ffffffff892c76e0 (
rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by kworker/1:1/38:
5 locks held by kworker/1:2/1121:
1 lock held by udevd/2851:
#0:
ffff888100ac5188
(&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
2 locks held by getty/2913:
#0:
ffff8881123ac0a0
(&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
1 lock held by syz-executor/2962:
#0: ffffffff892d2c78
(rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by syz-executor/2968:
1 lock held by syz-executor/2970:
#0:
ffffffff892d2c78
(
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
7 locks held by kworker/1:3/5224:
#0: ffff8881066f7948
((wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1:
ffffc9000215fd10
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffff88810b72c198
(&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: ffff8881236af198
(&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4:
ffff88811f4c5160
(
&dev->mutex){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5: ffffffff8a02cce8
(
input_mutex
){+.+.}-{4:4}
, at: class_mutex_intr_constructor include/linux/mutex.h:230 [inline]
, at: input_register_device+0x992/0x1180 drivers/input/input.c:2408
#6:
ffff888100ac5188
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:791
13 locks held by kworker/1:5/5288:
4 locks held by udevd/5392:
#0: ffff88811a49a668
(
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1:
ffff888111276088
(&of->mutex
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2:
ffff88813432cb48
(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: ffff8881236af198
(&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:916 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
2 locks held by syz.1.396/6102:
1 lock held by syz-executor/6109:
=============================================
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: 23 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:mark_lock+0x6/0x610 kernel/locking/lockdep.c:4714
Code: a0 61 1c 89 e8 0b c3 42 01 e9 4a fd ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 f0 48 83 ec 70 65 48 8b 05 6b 73 38
RSP: 0018:ffffc900001a8b98 EFLAGS: 00000002
RAX: 000000000000000c RBX: ffff888101ee61a8 RCX: 0000000000000004
RDX: 0000000000000008 RSI: ffff888101ee6298 RDI: ffff888101ee5700
RBP: ffffc900001a8ba0 R08: 0000000000080000 R09: 0000000000000001
R10: 00000000000000f0 R11: 0000000000000001 R12: ffff888101ee6298
R13: ffff888101ee5700 R14: 0000000000000006 R15: 0000000000000002
FS: 0000000000000000(0000) GS:ffff888268ff4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc4e51d1fe0 CR3: 0000000117262000 CR4: 00000000003506f0
Call Trace:
mark_usage kernel/locking/lockdep.c:4674 [inline]
__lock_acquire+0x3f8/0x1ce0 kernel/locking/lockdep.c:5191
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
debug_object_deactivate+0x135/0x3a0 lib/debugobjects.c:873
debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
debug_deactivate kernel/time/hrtimer.c:490 [inline]
__run_hrtimer kernel/time/hrtimer.c:1729 [inline]
__hrtimer_run_queues+0x46f/0xad0 kernel/time/hrtimer.c:1825
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
handle_softirqs+0x208/0x8d0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xfa/0x160 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x567/0x6d0 kernel/printk/printk.c:2449
Code: 00 4d 85 ed 0f 85 19 01 00 00 e8 54 7a 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 b2 75 20 00 48 85 ed 0f 85 25 01 00 00 34 7a 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc9000018f618 EFLAGS: 00000287
RAX: 000000000001364e RBX: 000000000000003c RCX: ffffc9001064c000
RDX: 0000000000100000 RSI: ffffffff815d81d6 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000031ec5
R13: 0000000000000200 R14: ffff888102685700 R15: ffffc9000018f6e0
dev_vprintk_emit drivers/base/core.c:4914 [inline]
dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925
__dev_printk+0xf5/0x270 drivers/base/core.c:4937
_dev_info+0xe4/0x120 drivers/base/core.c:4983
hub_port_init+0xcef/0x3b50 drivers/usb/core/hub.c:4995
hub_port_connect drivers/usb/core/hub.c:5495 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x2d84/0x5060 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
yealink 3-1:36.0: urb_irq_callback - urb status -71
yealink 3-1:36.0: unexpected response 0