Re: [PATCH 12/12] i386 boot: Add an ELF header to bzImage

Vivek Goyal
2006-10-04T14:25:26Z

On Wed, Oct 04, 2006 at 01:08:56AM -0600, Eric W. Biederman wrote:
> Vivek Goyal <vgoyal@in.ibm.com> writes:
>
> > Increasingly the cobbled together boot protocol that
> > is bzImage does not have the flexibility to deal
> > with booting in new situations.
> >
> > Now that we no longer support the bootsector loader
> > we have 512 bytes at the very start of a bzImage that
> > we can use for other things.
> >
> > Placing an ELF header there allows us to retain
> > a single binary for all of x86 while at the same
> > time describing things that bzImage does not allow
> > us to describe.
> >
> > The existing bugger off code for warning if we attempt to
> > boot from the bootsector is kept but the error message is
> > made more terse so we have a little more room to play with.
>
> Vivek for this first round can we please take out the ELF
> note processing. Now that vmlinux has ELF notes of interest
> to the bootloader we really should be getting the ELF notes
> from there.
>
> So the generation of the ELF notes needs to move into the
> vmlinux and then we need to copy them to ELF header.
>
> If we just remove the ELF note munging code from this patch
> that should be a good first step in getting the ELF notes correct.

Hi Eric,

Sure. I will get rid if ELF note generation for bzImage ELF header.

But would that stop bootloaders out there from treating kernel as
an ELF executable?

I have got a FC5 machine with grub version .97 and everything seems
to work for me. So I am assuming that Andrew got a newer version of
Grub which is trying to load ther kernel as an ELF executable and then
running into the issues.

Thanks
Vivek