INFO: task syz.0.4605:13909 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4605 state:D stack:0 pid:13909 tgid:13908 ppid:12611 flags:0x00000004
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: 0033:0x7fdd2418d550
RSP: 002b:00007fdd24f80b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000008041 RCX: 00007fdd2418d550
RDX: 0000000000008041 RSI: 00007fdd24f80c10 RDI: 00000000ffffff9c
RBP: 00007fdd24f80c10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007fdd243c6038 R14: 00007fdd243c5fa0 R15: 00007fff0d135598
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 487852573998b859d95f7a0f07f96e56ce6678e4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 36 Comm: kauditd Not tainted syzkaller #0 487852573998b859d95f7a0f07f96e56ce6678e4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:io_serial_in+0x7b/0xc0 drivers/tty/serial/8250/8250_port.c:406
Code: e8 da 9c 6d fe 44 89 f9 d3 e3 49 83 c6 08 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 eb c6 c3 fe 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f 5d e9 c5 03 76 02 cc 44 89 f9 80 e1
RSP: 0018:ffffc9000025f690 EFLAGS: 00000006
RAX: 1ffffffff113d905 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc9000025f6b0 R08: 0000000000000003 R09: 0000000000000004
R10: 0000000000000000 R11: ffffffff83184710 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff889ecde8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000001ae030 CR3: 0000000143426000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 000000008d00c0ed
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
serial_port_in include/linux/serial_core.h:794 [inline]
serial8250_console_write+0x328/0x2130 drivers/tty/serial/8250/8250_port.c:3386
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3151 [inline]
console_flush_all+0x5e6/0xaa0 kernel/printk/printk.c:3239
__console_flush_and_unlock kernel/printk/printk.c:3298 [inline]
console_unlock+0xe9/0x270 kernel/printk/printk.c:3338
vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2462
vprintk_default+0x2a/0x40 kernel/printk/printk.c:2477
vprintk+0x93/0xa0 kernel/printk/printk_safe.c:73
_printk+0xd0/0x120 kernel/printk/printk.c:2487
kauditd_printk_skb kernel/audit.c:546 [inline]
kauditd_hold_skb+0x1cc/0x230 kernel/audit.c:581
kauditd_send_queue+0x2c2/0x310 kernel/audit.c:766
kauditd_thread+0x4f0/0x740 kernel/audit.c:890
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