INFO: task syz.0.2529:7730 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2529 state:D stack:0 pid:7730 tgid:7729 ppid:290 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
device_lock include/linux/device.h:908 [inline]
usbdev_open+0x171/0x840 drivers/usb/core/devio.c:1051
chrdev_open+0x4de/0x5f0 fs/char_dev.c:414
do_dentry_open+0x978/0x1510 fs/open.c:960
vfs_open+0x86/0x230 fs/open.c:1090
do_open fs/namei.c:3774 [inline]
path_openat+0x2b6c/0x34b0 fs/namei.c:3933
do_filp_open+0x1c6/0x3e0 fs/namei.c:3960
do_sys_openat2+0x12c/0x1c0 fs/open.c:1438
do_sys_open fs/open.c:1453 [inline]
__do_sys_openat fs/open.c:1469 [inline]
__se_sys_openat fs/open.c:1464 [inline]
__x64_sys_openat+0x13a/0x170 fs/open.c:1464
x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f267978d590
RSP: 002b:00007f267a67cb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000101301 RCX: 00007f267978d590
RDX: 0000000000101301 RSI: 00007f267a67cc10 RDI: 00000000ffffff9c
RBP: 00007f267a67cc10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f26799d6038 R14: 00007f26799d5fa0 R15: 00007ffe86922b08
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 4fbf59849d479d82f8b5de9287114ed1a5b74461
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xd8f/0xed0 kernel/hung_task.c:423
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
cdc_ether 3-1:1.0 usb0: CDC: unexpected notification 9a!
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: kworker/1:0 Not tainted syzkaller #0 4fbf59849d479d82f8b5de9287114ed1a5b74461
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: wg-crypt-wg2 wg_packet_decrypt_worker
RIP: 0010:io_serial_out+0x85/0xd0 drivers/tty/serial/8250/8250_port.c:413
Code: fe 44 89 e1 41 d3 e6 49 83 c7 08 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 a4 83 c3 fe 45 03 37 89 d8 44 89 f2 ee <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 8c 4f 76 02 cc 44 89 e1 80 e1 07
RSP: 0018:ffffc90000230048 EFLAGS: 00000002
RAX: 000000000000002e RBX: 000000000000002e RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 000000000000c3a4 RDI: 000000000000c3a5
RBP: ffffc90000230070 R08: ffff888107ee8107 R09: 1ffff11020fdd020
R10: 0000000000000000 R11: ffffffff8318ab40 R12: 0000000000000000
R13: dffffc0000000000 R14: 00000000000003f8 R15: ffffffff889f2e28
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564556e15da8 CR3: 0000000107ee6000 CR4: 00000000003526b0
Call Trace:
serial_out drivers/tty/serial/8250/8250.h:142 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x166a/0x2130 drivers/tty/serial/8250/8250_port.c:3422
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3152 [inline]
console_flush_all+0x5e3/0xaa0 kernel/printk/printk.c:3240
__console_flush_and_unlock kernel/printk/printk.c:3299 [inline]
console_unlock+0xe9/0x270 kernel/printk/printk.c:3339
vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2463
dev_vprintk_emit+0x33b/0x400 drivers/base/core.c:4962
dev_printk_emit+0xe1/0x130 drivers/base/core.c:4973
__netdev_printk+0x3f2/0x4e0 net/core/dev.c:11899
netdev_err+0x10b/0x170 net/core/dev.c:11951
usbnet_cdc_status+0x3cf/0x4f0 drivers/net/usb/cdc_ether.c:436
intr_complete+0xe7/0x1d0 drivers/net/usb/usbnet.c:200
__usb_hcd_giveback_urb+0x400/0x600 drivers/usb/core/hcd.c:1650
usb_hcd_giveback_urb+0x11b/0x410 drivers/usb/core/hcd.c:1734
dummy_timer+0x822/0x4140 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1753 [inline]
__hrtimer_run_queues+0x3c0/0x9e0 kernel/time/hrtimer.c:1817
hrtimer_run_softirq+0x159/0x560 kernel/time/hrtimer.c:1834
handle_softirqs+0x1ab/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xa6/0x100 kernel/softirq.c:503
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
wg_packet_decrypt_worker+0x291/0xcd0 drivers/net/wireguard/receive.c:499
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d5/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
cdc_ether 3-1:1.0 usb0: CDC: unexpected notification db!