[libvirt] [PATCH] qemu: add support for -device pvpanic

[Daniel P. Berrange]

On Thu, Nov 28, 2013 at 04:09:00PM +0800, Hu Tao wrote:
> On Wed, Nov 27, 2013 at 06:15:27AM -0700, Eric Blake wrote:
> > On 11/27/2013 03:39 AM, Peter Krempa wrote:
> > > On 11/27/13 09:41, Hu Tao wrote:
> > >> qemu removes the builtin pvpanic device for all qemu versions since 1.7,
> > >> in order to support <on_crash>, '-device pvpanic' has to be added to
> > >> qemu command line.
> > >>
> > >> Signed-off-by: Hu Tao <hutao at cn.fujitsu.com>
> > >> ---
> > 
> > > I remember discussions saying that it's NOT a good idea to enable this
> > > stuff always. As a result, this device is not being added by qemu as you
> > > described above. Shouldn't we only add this if the user enables
> > > <on_crash> actions?
> > 
> > You are precisely right; we MUST add a new entry under <devices> in the
> > <domain> XML before enabling this device.
> 
> Is a entry under <devices> for pvpanic still needed? What I thought is
> that it is natural to enable pvpanic when user enables <on_crash>,
> he/she even has no need to know about pvpanic.

No, the <on_crash> elements are *soley* about setting policy. They
must never have any impact on hardware visibility.

Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|