[syslinux] Automatically choose between 32-bit and 64-bit kernel

[H. Peter Anvin]

Byron Stanoszek wrote:
> I've been using syslinux on my own Linux recovery CDs for almost a year now,
> and in that time I've found it useful to be able to automatically load a
> 64-bit-capable kernel if the CPU supports it.
> 
> I'd like to share my efforts and submit this patch for syslinux-3.31. It adds a
> new config file keyword, 'default64', which overrides the default image if a
> 64-bit CPU is detected. This allows your config file to have something like
> this in order to automatically choose between a 32-bit and 64-bit kernel:
> 
>       default linux
>       default64 linux64
>       prompt 0
> 
>       label linux
>         kernel vmlinuz
>         append root=/dev/sr0
> 
>       label linux64
>         kernel vmlinuz-64bit
>         append root=/dev/sr0
> 
> Alternatively, this patch can be grabbed from:
> http://www.winds.org/pub/linux/syslinux/syslinux-3.31-64bit.patch
> 

I really don't want to put this kind of stuff in the assembly code. 
There are arbitrary complex rules one may want to have for kernel 
selection, and that stuff belongs in a com32 module.

	-hpa