Re: XEN3_DOM0 rationalization

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sun, Mar 07, 2021 at 11:25:52AM -0800, John Nemeth wrote:
> On Mar 7, 13:47, Greg Troxel wrote:
> } 
> } Right now I think people need to read the HOWTO to figure out how to set
> } up Xen on NetBSD.  It's getting even more complicated with PVHVM and PVH
> 
>      Pretty much all complex software has some kind of learning
> curve.  I really don't view this as a negative.  Would you expect
> to be able to setup Asterisk, Samba, any other virtual environment,
> etc.  without doing some reading?
> 
>      PVHVM and PVH are in their infancy and can be ignored by most
> people for now.  I certainly wouldn't include them in the HOWTO at
> this point,  Also, last I knew we hadn't done much at all with PVH.
> The difference is PVHVM is domU running in HVM mode, but with access
> to PV devices (much more efficient since device emulation isn't
> needed).  Whereas PVH is for dom0 so that it runs in an HVM like
> mode.

No, PVH is for domU: like PHVVM but without qemu in the dom0.
This is mature on the Xen side, but not yet in a release on the NetBSD
side.

dom0 can be run in PVH mode too, but this is still considered experimental
on the Xen side (and only runs on a much more restried set of hardware than
domU PVH). The support on the NetBSD side is not complete yet (dom0 can boot
but the xentools don't work yet).

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--