Comment 15 for bug 656173

@nerling:

Whatever is creating the domain XML (ie with 'create' or 'define') needs to add the "<driver name='qemu' type='foo'/>" bit, after which it is stored in the XML. If OpenNebula creates virtual machines and adds them to libvirt, it must be adjusted for this. If OpenNebula is creating virtual machines, then it should know what type of disk format it is creating. If it always creates one format, then it is easy-- OpenNebula should just add "<driver name='qemu' type='opennubula's disk format'/>".

While I am the one commenting on these changes, I would like to reiterate that these are upstream changes and not Ubuntu specific. Yes, the behavior was changed in Lucid because it can be a significant security issue and Ubuntu users need to be protected. I suggest working with OpenNebula upstream to see how they are handling libvirt's new behavior, then patches can be applied to OpenNebula on Lucid (and possibly Maverick, if it is affected also) in an SRU (https://wiki.ubuntu.com/StableReleaseUpdates) or if the patch is simple enough it can be published in the security queue like was done for virtinst and vm-builder.