I am not an expert but libvirt is not only for qemu but it supports various virtualization technologies such as Xen, LXC, VMware. So if you decide to stick wit

I am not an expert but libvirt is not only for qemu but it supports various virtualization technologies such as Xen, LXC, VMware. So if you decide to stick with QEMU then I guess you don't need to use libvirt.