On Fri, Apr 27, 2007 at 11:02:44AM +0100, Richard W.M. Jones wrote: > Hugh Brock wrote: > >Maybe in the future we want to block or unblock them based on what's in > >the capabilities XML that comes out of libvirt? Be kind of a neat trick > >to work out that a fullvirt guest did in fact have a paravirt balloon > >driver involved, though... > > Capabilities statically describes what the hypervisor is capable of. It > doesn't say anything about what drivers, etc. happen to be loaded into > the guest. For that I guess you'd want to use virDomainGetXMLDesc (?) It is essentially impossible for Dom0 to know what capabilities (like device hotplug, paravirt disk, balloon) a guest VM has. When invoking operations like 'set-mem' the Dom0 control plan simply writes info into xenstored (eg changing the memory target). The guest VM needs a driver looking at that place in xenstored to effect the change. Dom0 has no idea whether there is such a driver. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|
