Hacking (downgrading to libvirt 0.7.0) libvirt/virsh/virt-manager/virt-install at Xen 4.0 Dom0 (2.6.32.12 pvops kernel ) on top of Ubuntu 10.04 Server

Due to ongoing issue with virsh compiled against libvirt 0.7.5 when working with Xen 4.0 Hypervisor. I attempted to downgrade libvirt and related stuff to Ubuntu Karmic’s ( well tested version with Xen). Proceed as follows :-

1.Edit /etc/apt/sources.list

Replace:
deb http://us.archive.ubuntu.com/ubuntu/ lucid main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ lucid main restricted
by
deb http://us.archive.ubuntu.com/ubuntu/ karmic main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ karmic main restricted

Save

# apt-get update
# apt-get install ubuntu-virt-server ubuntu-virt-mgmt ( from Karmic main)

2. Rebuild and reinstall Xen 4.0 & Tools

3. Reboot
KVM module fails to load

Revert /etc/apt/sources.list back as it was.
# apt-get update
You should get system with working virt-install and virt-manager.
Virsh should behave normal ( virsh list is not empty):

root@ServerLnx:/etc/apt# virsh version
Connecting to uri: xen:///
Compiled against library: libvir 0.7.0
Using library: libvir 0.7.0
Using API: Xen 3.0.1
Running hypervisor: Xen 4.0.0

root@ServerLnx:/etc/apt# virsh list
Connecting to uri: xen:///
Id Name State
———————————-
0 Domain-0 running
6 VMF12 idle