INFO: task syz.0.3818:11756 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3818 state:D stack:0 pid:11756 tgid:11704 ppid:11657 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
request_wait_answer fs/fuse/dev.c:476 [inline]
__fuse_request_send fs/fuse/dev.c:491 [inline]
__fuse_simple_request+0xdb1/0x1980 fs/fuse/dev.c:586
fuse_simple_request fs/fuse/fuse_i.h:1248 [inline]
fuse_lookup_name+0x2db/0x990 fs/fuse/dir.c:526
fuse_lookup+0x2ad/0x18f0 fs/fuse/dir.c:624
__lookup_slow+0x2d4/0x400 fs/namei.c:1732
lookup_one_len+0x19c/0x2f0 fs/namei.c:2851
incfs_lookup_dentry+0x64/0xc0 fs/incfs/data_mgmt.c:210
open_or_create_special_dir+0x4f/0x1e0 fs/incfs/vfs.c:455
incfs_mount_fs+0x4ad/0x960 fs/incfs/vfs.c:1876
legacy_get_tree+0x106/0x1b0 fs/fs_context.c:662
vfs_get_tree+0x9e/0x290 fs/super.c:1817
do_new_mount+0x251/0xb40 fs/namespace.c:3537
path_mount+0x688/0x1050 fs/namespace.c:3864
do_mount fs/namespace.c:3877 [inline]
__do_sys_mount fs/namespace.c:4087 [inline]
__se_sys_mount+0x2bd/0x480 fs/namespace.c:4064
__x64_sys_mount+0xc3/0xf0 fs/namespace.c:4064
x64_sys_call+0x2021/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:166
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: 0033:0x7f028a78eec9
RSP: 002b:00007f028b58e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f028a9e6090 RCX: 00007f028a78eec9
RDX: 0000200000000040 RSI: 0000200000000100 RDI: 0000200000000140
RBP: 00007f028a811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f028a9e6128 R14: 00007f028a9e6090 R15: 00007ffebdf555c8
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 a1e7228139d9ee8ddccd82caf3411206af300c09
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+0x2ca/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: 592 Comm: kworker/1:4 Not tainted syzkaller #0 a1e7228139d9ee8ddccd82caf3411206af300c09
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:serial8250_console_write+0x3a9/0x2130 drivers/tty/serial/8250/8250_port.c:3389
Code: 5c 24 20 41 c1 ee 06 41 83 e6 40 4c 89 e7 be 01 00 00 00 44 89 f2 41 ba d4 6f 31 c6 45 03 53 f1 74 02 0f 0b 2e e8 23 19 e8 1c <49> 8d 9c 24 70 02 00 00 48 89 d8 48 c1 e8 03 48 89 44 24 70 42 0f
RSP: 0018:ffffc9000f9cf040 EFLAGS: 00000006
RAX: 0000000000000000 RBX: ffffffff889f4e40 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000031ddc RDI: 0000000000031ddd
RBP: ffffc9000f9cf1c8 R08: 0000000000000003 R09: 0000000000000004
R10: 0000000000000000 R11: ffffffff8318f120 R12: ffffffff889f4e20
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff889f5078
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c251e27 CR3: 00000001275fe000 CR4: 00000000003526b0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0400000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
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+0x5e3/0xaa0 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
dev_vprintk_emit+0x33b/0x400 drivers/base/core.c:4962
dev_printk_emit+0xe1/0x130 drivers/base/core.c:4973
__dev_printk+0x17f/0x1b0 drivers/base/core.c:4985
_dev_err+0x10b/0x160 drivers/base/core.c:5028
hub_port_init+0x1297/0x27b0 drivers/usb/core/hub.c:-1
hub_port_connect drivers/usb/core/hub.c:5490 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5701 [inline]
port_event drivers/usb/core/hub.c:5865 [inline]
hub_event+0x232d/0x4270 drivers/usb/core/hub.c:5947
process_one_work kernel/workqueue.c:3237 [inline]
process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3318
worker_thread+0xc58/0x1250 kernel/workqueue.c:3399
kthread+0x2ca/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