Re: EFI and multiboot2 devlopment work for Xen
From: Konrad Rzeszutek Wilk
Date: Tue Oct 22 2013 - 12:36:32 EST
On Tue, Oct 22, 2013 at 03:25:39PM +0000, Woodhouse, David wrote:
> On Tue, 2013-10-22 at 10:43 -0400, Konrad Rzeszutek Wilk wrote:
> >
> > And looking at bit deeper in the x86/linux boot spec:
> >
> > **** EFI HANDOVER PROTOCOL
> >
> > This protocol allows boot loaders to defer initialisation to the EFI
> > boot stub. The boot loader is required to load the kernel/initrd(s)
> > from the boot media and jump to the EFI handover protocol entry point
> > which is hdr->handover_offset bytes from the beginning of
> > startup_{32,64}.
>
> Oh, ignore that. You want the *actual* PE executable entry point, as it
> would get invoked by a real UEFI firmware.
Right. The Xen hypervisor can be built in two images: a standard PE/COFF
that can be executed from the EFI shell, and an multiboot blob that can
be loaded by multiboot compatible boot loaders (like GRUB).
>
> I thought that's what Grub invoked, for 'linuxefi'. Perhaps I mean a
> chainloader method of some kind instead. Either way, make Grub (or
> whatever bootloader you choose) load it as an EFI executable.
Looks like chainloader was it from Peter's answer. But then you can't
do SecureBoot <sigh>.
>
> Seriously, forget Grub for now. Grub is mostly just an exercise in
> gratuitously doing things the difficult way and wondering why it's
> fragile.
>
> Make your code work as an EFI executable when loaded directly from the
> UEFI firmware. Worry about the insanity of grub later.
That has been done by Jan. Now we are at the 'have a shim that launches
GRUB2, now what?'
>
>
> --
> Sent with MeeGo's ActiveSync support.
>
> David Woodhouse Open Source Technology Centre
> David.Woodhouse@xxxxxxxxx Intel Corporation
>
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/