INFO: task udevd:2842 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller-11568-gd632ab86aff2 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D
stack:22072 pid:2842 tgid:2842 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+0x263/0x610 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/0x4b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe4de6933a7
RSP: 002b:00007ffdf9599ff8 EFLAGS: 00000246
ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007ffdf959a4d0 RCX: 00007fe4de6933a7
RDX: 0000000000000400 RSI: 00007ffdf959a000 RDI: 00007ffdf959a4d0
RBP: 00007ffdf959a000 R08: 0000000000000075 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 000055e430ed9100 R14: 00000000000000bd R15: 00007ffdf959bdd0
Showing all locks held in the system:
3 locks held by kworker/0:1/10:
1 lock held by khungtaskd/30:
#0: ffffffff890c72a0
(
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
1 lock held by udevd/2842:
2 locks held by getty/2906:
#0: ffff8881122f40a0
(
&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/2951:
1 lock held by syz-executor/2952:
1 lock held by syz-executor/2954:
1 lock held by syz-executor/2956:
1 lock held by syz-executor/2958:
3 locks held by kworker/0:4/5204:
5 locks held by kworker/1:2/5205:
#0:
ffff8881066f7948 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000427fd10
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2:
ffff88810b70c198
(&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: ffff88811f126198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:911 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4:
ffff888100ac5188
(
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:791
4 locks held by udevd/5207:
#0:
ffff888133ce01c8 (
&p->lock
){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1:
ffff88811cc42088
(&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2: ffff88811c5e4f08
(
kn->active
#9){++++}-{0:0}
, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3:
ffff88811f126198 (&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
5 locks held by kworker/1:3/5214:
1 lock held by udevd/5217:
4 locks held by kworker/1:4/5226:
#0: ffff888100080d48
((wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900041ffd10
(
kernfs_notify_work
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2:
ffff888100ac52b8 (
&root->kernfs_supers_rwsem
){++++}-{4:4}
, at: kernfs_notify_workfn+0xf7/0xb30 fs/kernfs/file.c:914
#3:
ffff888100ac5188
(&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_notify_workfn+0xff/0xb30 fs/kernfs/file.c:915
3 locks held by kworker/1:5/5236:
1 lock held by syz-executor/6350:
1 lock held by syz-executor/6351:
1 lock held by syz-executor/6352:
1 lock held by syz-executor/6353:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.16.0-syzkaller-11568-gd632ab86aff2 #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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+0x5b6/0x6c0 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:
yealink 4-1:36.0: unexpected response 0
yealink 4-1:36.0: urb_ctl_callback - urb status -71
yealink 4-1:36.0: urb_irq_callback - urb status -71
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2958 Comm: syz-executor Not tainted 6.16.0-syzkaller-11568-gd632ab86aff2 #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:401
Code: ae 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 c3 cc cc cc cc e8 58 d2 02 ff eb a2 e8 e1 d2
RSP: 0018:ffffc900001a8498 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff82d94f10 RDI: ffffffff9395e160
RBP: ffffffff9395e120 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff272bc7e R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff88826921d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f16af3650 CR3: 0000000008ea4000 CR4: 00000000003506f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0x137/0x210 drivers/tty/serial/8250/8250_port.c:1984
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3288 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3311 [inline]
serial8250_console_write+0xf81/0x1890 drivers/tty/serial/8250/8250_port.c:3396
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x7fe/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
__dev_printk+0xf5/0x270 drivers/base/core.c:4937
_dev_err+0xe4/0x120 drivers/base/core.c:4980
urb_irq_callback+0x454/0x700 drivers/input/misc/yealink.c:418
__usb_hcd_giveback_urb+0x38a/0x6e0 drivers/usb/core/hcd.c:1663
usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1747
dummy_timer+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x1ff/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:__tlb_remove_folio_pages_size.constprop.0+0x23/0x560 mm/mmu_gather.c:171
Code: 90 90 90 90 90 90 90 41 57 41 56 41 55 41 54 41 89 d4 55 89 cd 53 48 89 fb 48 83 ec 18 48 89 34 24 e8 11 e9 b2 ff 48 8d 7b 18 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f
RSP: 0018:ffffc9000184f5d8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffc9000184fab0 RCX: 0000000000000000
RDX: ffff8881122d8000 RSI: ffffffff81cb144f RDI: ffffc9000184fac8
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffffc9000184f7a8 R14: 00007f8b1cd2b000 R15: 0000000000000000
zap_present_folio_ptes mm/memory.c:1528 [inline]
zap_present_ptes mm/memory.c:1581 [inline]
do_zap_pte_range mm/memory.c:1682 [inline]
zap_pte_range mm/memory.c:1726 [inline]
zap_pmd_range mm/memory.c:1818 [inline]
zap_pud_range mm/memory.c:1847 [inline]
zap_p4d_range mm/memory.c:1868 [inline]
unmap_page_range+0x1266/0x3650 mm/memory.c:1889
unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:1932
unmap_vmas+0x218/0x470 mm/memory.c:1976
exit_mmap+0x1b9/0xb90 mm/mmap.c:1280
__mmput kernel/fork.c:1126 [inline]
mmput+0xdb/0x430 kernel/fork.c:1149
exit_mm kernel/exit.c:582 [inline]
do_exit+0x7c7/0x2bf0 kernel/exit.c:949
do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x7c/0xe0 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x3e9/0x4b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b1db1e4e1
Code: Unable to access opcode bytes at 0x7f8b1db1e4b7.
RSP: 002b:00007ffca56270a0 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
RAX: fffffffffffffffe RBX: 00000000000000c6 RCX: 00007f8b1db1e4e1
RDX: 0000000000090800 RSI: 00007f8b1dba210e RDI: 00000000ffffff9c
RBP: 00007ffca562714c R08: 000000000000b6d4 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000287 R12: 0000000000000041
R13: 0000000000000000 R14: 000000000003c76a R15: 00007ffca56271a0