Re: PvGRUB2 on Arm64?

[Julien Grall <julien@xxxxxxx>]

Hi Benjamin,

On 07/10/2022 21:33, Benjamin Mordaunt wrote:
> On Fri Oct 7, 2022 at 4:53 PM BST, Julien Grall wrote:
> > Hi Benjamin,
> >
> > On 07/10/2022 16:38, Benjamin Mordaunt wrote:
> > > On 07/10/2022 11:42, Julien Grall wrote:
> > >
> > > > We have support for UEFI/U-boot in the guest. With that you should be
> > >    > able to launch a normal GRUB. Would that work for you?
> > >
> > > I’m struggling to interpret Xen’s documentation around EFI Guest support on 
> > > arm64.
> > >
> > > You claim that it exists, and sure enough I can find resources for EFI Xen Host,
> > > but in
> > >
> > > terms of DomU, I see OVMF for x86, but don’t see anything for Arm.
> > >
> > > Can you give any pointers?
> > The EDK2 platform is ArmVirtPkg/ArmVirtXen.dsc. Unfortunately, I don't
> > have the instructions at hand.
> >
> > To build the EFI firmware, you should be able to use instructions in [1]
> > and then use "Xen" rather than QEMU. The blob provided could be used by
> > replacing adding as the kernel in the xl configuration file.
> >
> > Note that I haven't used EDK2 recently. So I can't guarantee this work.
> > Although, I should be able to help if there are any issues.
> >
> > Cheers,
> >
> > [1] https://www.kraxel.org/blog/2022/05/edk2-virt-quickstart/
> >
> > --
> > Julien Grall
> Hi Julien, apologies I haven't expressed my requirements properly. I
> have a system which boots via U-Boot (in theory, it could boot through
> EFI, but that would involve changing a lot of configuration).
>
> What I really wanted was the following flow:
>
> U-Boot -> Xen -> EFI (for guest) -> GRUB -> Ubuntu
>
> Is this possible, or do we need to use EFI at the top level?
Yes this is possible. The guest firmware doesn't depened on the host 
firmware.
Cheers,

--
Julien Grall