Re: EFI and multiboot2 devlopment work for Xen

[Ian Campbell <ian.campbell@citrix.com>]

On Tue, 2013-10-22 at 10:09 -0400, Konrad Rzeszutek Wilk wrote:

> So it can be booted the same way as xen.efi. But my understanding is
> that folks prefer a bootloader instead of loading the bzImage in an
> NVRAM of a platform with pre-set parameters. Hence that mechanism
> is not used by the majority of users.

My understanding is that they prefer a bootloader which can launch Linux
as a PE/COFF image, i.e. the linuxefi thing.

> Instead the majority of users would like to use a bootloader, like
> GRUB2. And there are certain restrictions - if you launch from it
> an PE/COFF application GRUB2 will call ExitBootServices. But if
> you launch the Linux image (so using the linuxefi), it WILL NOT
> call ExitBootServices.

"linuxefi" won't call ExitBootServices but it will launch as a PE/COFF
application not as a "Linux image", that's right isn't it? I think that
is the whole point of it.

The "launch as a Linux image" grub command is called just "linux" (and
"kernel" may be a synonym).

> But I say that (about ExitBootServices) - and I can't find it in
> the GRUB2 code, so perhaps I am mistaken.

linuxefi isn't in the upstream grub2 tree -- all the distros are
carrying it as a patch. So if you are grepping upstream you won't find
it.

Ian.