To use looking glass, you need to enable IVSHMEM as follows:

  1. Open your xml in an editor:
    ​# virsh edit {guest}
  2. ​Include qemu’s XML namespace declaration in the ‘domain’ root element:
    <domain type=’kvm’ xmlns:qemu=’http://libvirt.org/schemas/domain/qemu/1.0′>
  3. In the domain element, add IVSHMEM:
    <qemu:commandline>
     <qemu:arg value=’-device’/>
     <qemu:arg value=’ivshmem-doorbell,chardev=ivshmem,vectors=1’/>
     <qemu:arg value=’-chardev’/>
     <qemu:arg value=’socket,path=/tmp/ivshmem_socket,id=ivshmem’/>
    </qemu:commandline>
  4. Start the IVSHMEM server on the host (adjust values as necessary):
    ivshmem-server -p /tmp/ivshmem.pid -S /tmp/ivshmem_socket -l 16M -n 8