Re: [PATCH 0/5] Add second memory region for crash kernel

[Vivek Goyal <vgoyal@redhat.com>]

On Thu, Apr 22, 2010 at 05:48:53PM -0700, Eric W. Biederman wrote:
> Vivek Goyal <vgoyal@redhat.com> writes:
> 
> > On Thu, Apr 22, 2010 at 03:07:11PM -0700, Eric W. Biederman wrote:
> >> Vitaly Mayatskikh <v.mayatskih@gmail.com> writes:
> >> >
> >> > This serie of patches realizes this approach. It requires also changes
> >> > in kexec utility to make this feature work, but is
> >> > backward-compatible: old versions of kexec will work with new
> >> > kernel. I will post patch to kexec-tools upstream separately.
> >> 
> >> Have you tried loading a 64bit vmlinux directly into a higher address
> >> range?  There may be a bit or two missing but you should be able to
> >> load a linux kernel above 4GB.  I tested the basics of that mechanism
> >> when I made the 64bit relocatable kernel.
> >
> > I guess even if it works, for distributions it will become additional
> > liability to carry vmlinux (instead of relocatable bzImage). So we shall
> > have to find a way to make bzImage work.
> 
> As Peter pointed out we actually have everything thing we need except
> a bit of documentation and the flag that says this is a 64bit kernel.
> 
> >From a testing perspective a 64bit vmlinux should work today without
> changes.  Once it is confirmed there is a solution with the 64bit
> kernel we just need a small patch to boot.txt and a few tweaks to 
> /sbin/kexec to handle a 64bit bzImage.
> 

Agreed. Doing little more testing and fixing some issues, if need be, and
making 64 bzImage work is the better way instead of splitting the reserved
memory.
 
Thanks
Vivek