我正在使用从 Builtroot 构建的图像，并使用 QEMU 运行。但是当我运行“poweroff”命令时，机器没有关机。并出现“系统停止”！（见下面的控制台输出）
# poweroff
# Stopping network: OK
Saving random seed: random: dd: uninitialized urandom read (512 bytes read)
OK
Stopping klogd: OK
Stopping syslogd: OK
umount: devtmpfs busy - remounted read-only
EXT4-fs (sda): re-mounted. Opts: (null)
The system is going down NOW!
Sent SIGTERM to all processes
Sent SIGKILL to all processes
Requesting system poweroff
sd 0:0:0:0: [sda] Synchronizing SCSI cache
reboot: System halted
有人能帮我吗？谢谢！