Comment 15 for bug 665531

Uhm... this "fix" for Lucid (and therefore probably the older one in 0.7.5-5ubuntu27.5) did really break a working system!!

We had a running system with Opennebula/KVM/libvirt and after last upgrade
     libvirt 0.7.5-5ubuntu27.3 ----> 0.7.5-5ubuntu27.7
creating virtual machines didn't work anymore for qcow2 images...

I don't discuss if "format=host_device" should be supported or not, but in any case the changes affecting it were IMHO unnecessary in a stable release like Lucid!! I confidently perform updates on a stable release expecting the system to keep working, we were forced to downgrade libvirt to the lucid/release version to get it working again.

With Debian that would not happen ;-)