Comment # 3 on bug 1181333 from James Fehlig

(In reply to Bart Van Assche from comment #2)
> Thanks for having taken a look. Enabling libvirtd networking failed because
> of another reason (firewalld issue). I agree that libvirtd started
> successfully. In other words, the only issue here is that the following
> message is reported: "Failed to initialize libnetcontrol.  Management of
> interface devices is disabled".

Ok. If you want that message to go away then use wicked instead of
NetworkManager for your host network management.