[libvirt-users] how to use LV(container) created by lxc-create?

hi everyone, how can I use a LV created by lxc in libvirt guest domain? You know, you lxc-create with LV as backstore for a container(ubuntu in my case) and now you want to give to libvit. That, I thought would be a very common case but I failed to find a good howto on how one: lxc-create(lvm) => let libvirt take control over it. Or it's not how you would do it at all? many thanks, L.