On Tue, Jul 20, 2010 at 08:59:29AM -0600, Eric Blake wrote: > On 07/20/2010 08:49 AM, Daniel P. Berrange wrote: > > On Tue, Jul 20, 2010 at 10:39:01AM -0400, Cole Robinson wrote: > >> On 07/20/2010 09:09 AM, Daniel P. Berrange wrote: > >>> From: Daniel P. Berrange <dan@xxxxxxxxxxxx> > >>> > >>> To allow compatability with older QEMU PCI device slot assignment > >>> it is neccessary to explicitly track the balloon device in the > >>> XML. This introduces a new device > >>> > >>> <memballoon model='virtio|xen'/> > >>> > >>> It can also have a PCI address, auto-assigned if neccessary. > >>> > >>> The memballoon will be automatically added to all Xen and QEMU > >>> guests by default. > >>> > >> > >> Is there a way for users to remove/disable the balloon device? Certainly > >> doesn't block this patch, but someone is going to ask for it eventually. > > > > There isn't an easy way to allow for this without breaking back > > compatability. We have always enabled the balloon driver, even > > though nothing was in the XML. Thus we can't simply leave out > > the '<memballoon>' element and expect the balloon to go away > > as that would break compat. > > You are correct that we can't remove XML to remove the feature, but we > can add some. What about using <memballoon model='none'/> as a way to > explicitly request that it be excluded? Sure, but that's what I meant by not easy - that kind of thing is really disgusting. Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list