INFO: task udevd:2858 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:26552 pid:2858 tgid:2858 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xeb0/0x3e50 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
rwsem_down_read_slowpath+0x5dc/0xb30 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1261 [inline]
__down_read kernel/locking/rwsem.c:1274 [inline]
down_read+0xed/0x460 kernel/locking/rwsem.c:1539
kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185
d_revalidate fs/namei.c:977 [inline]
d_revalidate fs/namei.c:973 [inline]
lookup_fast+0x3c7/0x600 fs/namei.c:1827
walk_component fs/namei.c:2225 [inline]
link_path_walk+0x7a8/0x1b30 fs/namei.c:2597
path_openat+0x1be/0x3120 fs/namei.c:4792
do_filp_open+0x1f7/0x420 fs/namei.c:4823
do_sys_openat2+0x12e/0x220 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x570 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1061bbb407
RSP: 002b:00007ffcdb143020 EFLAGS: 00000202
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1061acd880 RCX: 00007f1061bbb407
RDX: 0000000000080000 RSI: 00007ffcdb1431a0 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055bb042ba7f5
R13: 000055bb042ba7f5 R14: 0000000000000001 R15: 0000000000000000
INFO: task syz-executor:2966 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D
stack:24968 pid:2966 tgid:2966 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xeb0/0x3e50 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
rwsem_down_read_slowpath+0x5dc/0xb30 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1261 [inline]
__down_read kernel/locking/rwsem.c:1274 [inline]
down_read+0xed/0x460 kernel/locking/rwsem.c:1539
kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185
d_revalidate fs/namei.c:977 [inline]
d_revalidate fs/namei.c:973 [inline]
lookup_fast+0x3c7/0x600 fs/namei.c:1827
walk_component fs/namei.c:2225 [inline]
link_path_walk+0x7a8/0x1b30 fs/namei.c:2597
path_openat+0x1be/0x3120 fs/namei.c:4792
do_filp_open+0x1f7/0x420 fs/namei.c:4823
do_sys_openat2+0x12e/0x220 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x570 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14aeb4b94c
RSP: 002b:00007ffcdb0bd090 EFLAGS: 00000206
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000044 RCX: 00007f14aeb4b94c
RDX: 0000000000090800 RSI: 00007f14aebe247b RDI: 00000000ffffff9c
RBP: 00007ffcdb0bd13c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000017
R13: 0000000000000000 R14: 000000000002149d R15: 00007ffcdb0bd190
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0:
ffffffff894da3a0 (
rcu_read_lock){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
5 locks held by kworker/1:1/38:
2 locks held by kworker/u8:5/165:
#0:
ffff888100089148
((wq_completion)events_unbound
#2){+.+.}-{0:0}
, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1:
ffffc9000155fca8 (
(work_completion)(&sub_info->work)
){+.+.}-{0:0}
, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
2 locks held by kworker/1:2/1120:
1 lock held by udevd/2858:
#0:
ffff888100ac5988
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185
2 locks held by getty/2920:
#0:
ffff888115b810a0 (
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900000452f0
(
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/2966:
#0:
ffff888100ac5988 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167
1 lock held by syz-executor/2968:
#0:
ffff888100ac5988
(&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167
1 lock held by syz-executor/2969:
#0:
ffff888100ac5988
(
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167
1 lock held by syz-executor/2970:
#0: ffff888100ac5988
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167
1 lock held by syz-executor/2974:
#0:
ffff888100ac5988 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167
4 locks held by udevd/5201:
#0:
ffff8881136fae80
(&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182
#1: ffff88811f5e4088
(&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2:
ffff888109ea2c38
(
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: ffff88811b120198
(
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:900 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by udevd/5209:
8 locks held by kworker/1:3/5225:
3 locks held by kworker/0:4/5234:
3 locks held by kworker/1:4/5259:
1 lock held by syz.3.108/5556:
#0: ffffffff894e6b78
(rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by syz-executor/5558:
1 lock held by syz-executor/5559:
1 lock held by syz-executor/5560:
1 lock held by syz-executor/5561:
=============================================
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 02/12/2026
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:161 [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:346 [inline]
watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
yealink 3-1:36.0: urb_irq_callback - urb status -71
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1120 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:407
Code: 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 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 d1 6a 01 ff eb a0 e8 5a 6b 01
RSP: 0018:ffffc900001a8450 EFLAGS: 00000002
RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: ffffffff8311c005 RDI: ffffffff93f14fc0
RBP: ffffffff93f14f80 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 000000000000005b R14: 0000000000000010 R15: ffffffff8311bfa0
FS: 0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f106185e5e6 CR3: 00000000092a8000 CR4: 00000000003506f0
Call Trace:
serial_port_out include/linux/serial_core.h:811 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3192 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3264 [inline]
serial8250_console_write+0xde8/0x1900 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3129 [inline]
console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3215
console_flush_all kernel/printk/printk.c:3289 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0x103/0x260 kernel/printk/printk.c:3359
vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426
dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4914
dev_printk_emit+0xd2/0x10d drivers/base/core.c:4925
__dev_printk+0xcb/0x100 drivers/base/core.c:4937
_dev_err+0xef/0x127 drivers/base/core.c:4980
urb_irq_callback.cold+0x41/0xfd drivers/input/misc/yealink.c:418
__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+0xd85/0x3670 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x516/0x990 kernel/time/hrtimer.c:1841
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
handle_softirqs+0x1dd/0x8f0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xed/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:schedule_debug kernel/sched/core.c:5819 [inline]
RIP: 0010:__schedule+0x17d/0x3e50 kernel/sched/core.c:6744
Code: 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 82 39 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 7c 24 20 4c 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 55 39 00 00 49 81 3f 9d 6e ac 57 0f 85 97 3c 00 00 49 8d 4c
RSP: 0018:ffffc90001aef9d8 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff8881f57390c0 RCX: ffffffff87544e5e
RDX: 1ffff9200035d000 RSI: ffffffff878e9720 RDI: ffff88810eb71d60
RBP: ffffc90001aefab8 R08: 0000000000000000 R09: fffffbfff1599aba
R10: ffffffff8accd5d7 R11: 0000000000000000 R12: ffff88810eb71d40
R13: 0000000000000001 R14: ffffffff8cccf0c0 R15: ffffc90001ae8000
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7051
__cond_resched+0x22/0x30 kernel/sched/core.c:7378
_cond_resched include/linux/sched.h:2061 [inline]
gc_worker+0x96b/0x1630 net/netfilter/nf_conntrack_core.c:1618
process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246