Re: [PATCH 0/3] x86/xen: support booting PVH guest via standard boot path

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

On 11/08/2017 08:40 AM, Juergen Gross wrote:
> On 08/11/17 14:37, Boris Ostrovsky wrote:
>> On 11/08/2017 04:07 AM, Juergen Gross wrote:
>>> Booting a Xen PVH guest requires a special boot entry as it is
>>> mandatory to setup some Xen-specific interfaces rather early. When grub
>>> or OVMF are used as boot loaders, however, those will fill the boot
>>> parameters in zeropage and there is no longer a need to do something
>>> PVH specific in the early boot path.
>>>
>>> This patch series adds support for that scenario by identifying PVH
>>> environment and doing the required init steps via Xen hooks instead of
>>> using a dedicated boot entry.
>>>
>>> The dedicated entry is still needed for support of Dom0 running in PVH
>>> mode as in this case there is no grub or OVMF involved for filling in
>>> the boot parameters.
>> We are going to continue supporting direct boot of unprivileged guests
>> too so this entry point will be needed not for dom0 only.
> Sure, but using e.g. grub in this case would be an alternative. For Dom0
> this alternative isn't existing. So this entry is mandatory, not a "nice
> to have".

Right, I was just pointing out that the way the message is phrased makes
it sounds (to me at least) as if dom0 is the only reason for the
dedicated entry point.

-boris