用 balena etcher，从iso制作 U 盘启动盘（显示missing partition table
It looks like this is not a bootable image. The image does not appear to contain a partition table, and might not be recognized or bootable by your device）在恢复模式下打开非安全启动选项后无法识别启动盘。用 sudo dd 命令重制启动盘仍不行