INT 13, real mode, block write commands and coreboot

[Vincent Legoll]

Why don't you use another arch computer to dump the usb key content
into a file, you won't have to wonder if it got modified by a BIOS.

A raspberry pi or any other such SBCs will do just fine for that.

Plug it in, dump it without mounting any eventual partitions, and you're
done.

You can derive from threre for other interfaces like SATA...