Re: [Xen-devel] [PATCH RFC] tools/libxl: Switch Arm guest type to PVH

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Mon, 2 Jul 2018, Julien Grall wrote:
> On 06/26/2018 07:49 AM, Roger Pau Monné wrote:
> > On Mon, Jun 25, 2018 at 05:39:12PM +0100, Ian Jackson wrote:
> > > Roger Pau Monné writes ("Re: [PATCH RFC] tools/libxl: Switch Arm guest
> > > type to PVH"):
> > > > IMO I would remove the 'type' option from xl.cfg (so that it's
> > > > basically ignored) in the ARM case and force it internally to PVH (if
> > > > that's the best route for current ARM guests).
> > > 
> > > What about libvirt users ?  I haven't seen what a libvirt Xen ARM
> > > guest config looks like but we need to meak sure that existing guests
> > > don't break.
> > 
> > For livbirt (or users of libxl library) we could force the type to
> > pvh, regardless of the value set by the client, but I guess that would
> > make adding types later on quite complicated.
> 
> I am fairly confident we will never have PV guest on Arm. So one solution
> would be to alias PV to PVH for Arm. This still give us the liberty to add
> more guest type in the future.
> 
> Any opinions?

Roger, what is the plan for x86? Wasn't there an idea to silently and
transparently "upgrade" PV guests to PVH when possible (when hardware
support is available)?

If that is the case, basically we could do the same for ARM. We could
have an hardware features check, that would always return true on ARM
because without virtualization extensions Xen cannot even boot, then
upgrade PV to PVH. On x86 the upgrade would only happen when the
required features are present.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel