Re: HVM virtualization?

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

On Sat, Oct 31, 2020 at 06:36:45PM -0400, Greg Troxel wrote:
> 
> Manuel Bouyer <bouyer%antioche.eu.org@localhost> writes:
> 
> > On Sat, Oct 31, 2020 at 01:37:17PM -0500, Jeremy C. Reed wrote:
> >> One of my hosting providers is converting VPSes from PV to HVM 
> >> virtualization due to security issue
> >> https://xenbits.xen.org/xsa/advisory-286.html
> >> 
> >> They say NetBSD does not work under HVM mode and can choose a different 
> >> BSD (or Linux).
> >> 
> >> Can someone tell me about this? I did look briefly at 
> >> http://wiki.netbsd.org/ports/xen/howto/ but don't understand the context 
> >> of the wiki saying it is supported but the hosting provider saying it 
> >> does not work.
> >
> > plain HVM, with emulated devices, works without problems (and always has).
> > If they only support PV devices, then it works only in HEAD (GENERIC supports
> > it)
> 
> I have heard that the issue with with qemu "stub domains" and with
> those, NetBSD ends up with PIO on disks and is thus unusably slow.
> 
> https://wiki.xen.org/wiki/QEMU_vs_qemu-traditionnal_Feature_Comparison

So running a HEAD GENERIC, which has the PV drivers, would solve this.

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