[PATCH v3 4/4] kexec, x86_64: Load bzImage64 above 4G

[Vivek Goyal]

On Wed, Nov 21, 2012 at 11:50:56AM -0800, Yinghai Lu wrote:

[..]
> > So how do I force a 16bit or 32bit entry using a bzImage64?
> 
> kexec -t bzImage -l ....
> will load low and use 32bit entry.
> 

Ok, so user needs to enforce image type (using -t option) to bzImage
(for a bzImage which supports 64bit entry point) to be able to use
32bit entry.

I think a better option is that bzImage64 loader parses the user specified
entry options and call into 32bit bzImage loader if user is asking for 32bit
or 16bit entry. For 16bit, we already have option --real-mode option. May
be we need to introduce another one for forcing 32bit entry, say --entry-32bit
or --protected-mode (whatever makes sense).

Eric will know better but I do think that bzImage64 loader should be able
to parse user specified entry point and honor that.

> kexec -t bzImage64 -l ...
> kexec -l ...
> will try to load high and use 64bit entry.

This one violates the existing syntax where --real-mode is supposed to
jump to real mode entry point of bzImage.

Eric will know better but I do think that bzImage64 loader should be able
to parse user specified entry point and honor that.

Thanks
Vivek