INFO: task syz.1.4483:21620 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.4483 state:D stack:26280 pid:21620 tgid:21611 ppid:14082 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
request_wait_answer fs/fuse/dev.c:567 [inline]
__fuse_request_send fs/fuse/dev.c:581 [inline]
__fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:675
fuse_simple_request fs/fuse/fuse_i.h:1247 [inline]
fuse_do_getattr+0x33b/0x620 fs/fuse/dir.c:1317
fuse_update_get_attr+0x518/0x10f0 fs/fuse/dir.c:1374
vfs_getattr_nosec+0x2de/0x430 fs/stat.c:213
ubi_get_num_by_path+0x102/0x2e0 drivers/mtd/ubi/kapi.c:300
ubi_open_volume_path+0x88/0x1a0 drivers/mtd/ubi/kapi.c:334
open_ubi fs/ubifs/super.c:2045 [inline]
ubifs_get_tree+0x109/0x7080 fs/ubifs/super.c:2251
vfs_get_tree+0x8f/0x2b0 fs/super.c:1752
do_new_mount+0x2a2/0xa30 fs/namespace.c:3810
do_mount fs/namespace.c:4138 [inline]
__do_sys_mount fs/namespace.c:4349 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4326
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8ec478ebe9
RSP: 002b:00007f8ec553a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f8ec49c6090 RCX: 00007f8ec478ebe9
RDX: 0000200000000080 RSI: 0000200000000000 RDI: 00002000000000c0
RBP: 00007f8ec4811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ec49c6128 R14: 00007f8ec49c6090 R15: 00007fff8e0494a8
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5859 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 5e 47 66 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 0f f1 c9 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc9000416f318 EFLAGS: 00000006
RAX: 1ffffffff3448c05 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc9000416f4f0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff855a8720 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff9a246080 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881257c4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feb715212c0 CR3: 0000000034cdc000 CR4: 00000000003526f0
Call Trace:
serial_port_in include/linux/serial_core.h:806 [inline]
serial8250_console_write+0x581/0x1ba0 drivers/tty/serial/8250/8250_port.c:3306
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline]
m920x_rc_query+0x2f6/0x830 drivers/media/usb/dvb-usb/m920x.c:-1
legacy_dvb_usb_read_remote_control+0xfd/0x470 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245