Re: [Etherboot-developers] booting non linux images

[Ken Y. <ke...@bi...>]

>Actually the bootsect.S and setup.S _are_ sligntly changed versions of
>corresponding Linux files. They even carry the copyright message of Linus
>Torvalds.
>
>mknbi-linux reports that it is not a Linux kernel image. Actually I tried
>to _blindly_ build it with the build program of a newer linux kernel, but
>this didn't work. I am now trying the problem in a more methodical way.

That's probably because it didn't find various magic numbers in the
bootblock or the setup segment. See which one it's complaining about,
and temporarily disable the check in mknbi.pl.

>First I wrote a small C program (well, to be honest, I am not at all good
>in Perl, althogh I use C, shell scripting and PHP extensively) to compare
>two binary files and find equal regions. Using this and hexdump I am
>comparing a real linux kernel and a tagged one with mknbi-linux. This
>shows that a tagged immage is a header plus the original image. If I am to
>write a program mknbi.memtest86 (in C), will I have to first write the
>header and "append" the "kernel" to it?

Sure, but as I said, you'd have better luck modifying mknbi.pl.

>BTW, please let me know if the documentation regarding a tagged images
>_with_ a first magic number is correct and whether etherboot handles them
>(unlike the ones with a second magic number)?

Yes, it is correct.