Re: HVMLite / PVHv2 - using x86 EFI boot entry

From: Daniel Kiper
Date: Wed Apr 06 2016 - 07:12:50 EST


On Wed, Apr 06, 2016 at 04:40:27AM +0200, Luis R. Rodriguez wrote:
> Boris sent out the first HVMLite series of patches to add a new Xen guest type
> February 1, 2016 [0]. We've been talking off list with a few folks now over
> the prospect of instead of adding yet-another-boot-entry we instead fixate
> HVMLite to use the x86 EFI boot entry. There's a series of reasons to consider
> this, likewise there are reasons to question the effort required and if its
> really needed. We'd like some more public review of this proposal, and see if
> others can come up with other ideas, both in favor or against this proposal.
>
> This in particular is also a good time to get x86 Linux folks to chime on on
> the general design proposal of HVMLite design, given that outside of the boot
> entry discussion it would seem including myself that we didn't get the memo
> over the proposed architecture review [1]. At least on my behalf perhaps the
> only sticking thorns of the design was the new boot entry, which came to me
> as a surprise, and this thread addresses and the lack of addressing semantics
> for early boot (which we may seem to need to address; some of this is being
> addressing in parallels through other work). The HVMLite document talks about
> using ACPI_FADT_NO_VGA -- we don't use this yet upstream but I have some pending
> changes which should make it easy to integrate its use on HVMLite. Perhaps
> there are others that may have some other points they may want to raise now...
>
> A huge summary of the discussion over EFI boot option for HVMLite is now on a
> wiki [2], below I'll just provide the outline of the discussion. Consider this a
> request for more public review, feel free to take any of the items below and
> elaborate on it as you see fit.
>
> Worth mentioning also is that this topic will be discussed at the 2016 Xen
> Hackathon April 18-19 [3] at the ARM Cambridge, UK Headquarters so if you can
> attend and this topic interests you, consider attending.

I hope that you will be there as one of the biggest proponents of EFI entry point.
If you does not it will be difficult or impossible to discuss this issue without you.
In the worst case I can raise this topic on behalf of you and then we should organize
phone call if possible (and accepted by others). However, to do that I must know your
plans in advance.

Daniel