Re: [Qemu-devel] [Xen-devel] [PATCH] Remove hardcoded xen-platform device initialization

[Paul Durrant <Paul.Durrant@citrix.com>]

> -----Original Message-----
> From: Paolo Bonzini [mailto:paolo.bonzini@gmail.com] On Behalf Of Paolo
> Bonzini
> Sent: 13 June 2013 19:03
> To: Ian Campbell
> Cc: Stefano Stabellini; Paul Durrant; qemu-devel@nongnu.org; xen-
> devel@lists.xen.org
> Subject: Re: [Xen-devel] [PATCH] Remove hardcoded xen-platform device
> initialization
> 
> Il 13/06/2013 13:44, Ian Campbell ha scritto:
> > On Thu, 2013-06-13 at 18:33 +0100, Stefano Stabellini wrote:
> >> On Thu, 13 Jun 2013, Paul Durrant wrote:
> >>> The xen-platform device should be initialized by the Xen toolstack by
> >>> passing the appropriate -device argument on the command line.
> >>>
> >>> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> >>
> >> This patch is problematic because we can't know for sure the version of
> >> upstream QEMU that is going to be used with Xen.
> >> If we apply this patch and QEMU 1.5 is going to be used with Xen 4.2,
> >> guests won't be able to use PV drivers.
> >
> > Is the right answer a lever to disable, rather than enable, it?
> >
> > A workaround for the situation you envisage is to use the
> > device_model_args config option, not ideal though.
> 
> I think the right solution for this is to move towards using the normal
> "-M pc" machine.  libxl can simply use "-M pc -machine accel=xen -device
> xen-platform-pv"; older versions that use the xenfv machine will still work.
> 
> And if you do this, you will also get the benefit of versioned machine
> types.
> 

Thanks. I'll have a look at that.

  Paul