[libvirt-users] Are more then one overlay possible without recieving a "Permission denied"?

I've created a backing chain like this. FirstFollr.ovl is an overlay to Base.img and so on. Base.img (ok - Win 10 Installation starting) FirstFloor.ovl (ok - Win 10 Installation starting) SecondFloor.ovl (permission denied -> Base.img) => assumed Bug Roof.ovl (permission denied -> Base.img) => assumed Bug Using virsh / virt-manager, I can only start Base and FirstFloor. Starting Second and Roof are failing. What's wrong? Details are described in: https://bugzilla.redhat.com/show_bug.cgi?id=1588373 System infos: Compiled against library: libvirt 4.0.0 Using library: libvirt 4.0.0 Using API: QEMU 4.0.0 Running hypervisor: QEMU 2.11.1 Ubuntu 18.04 LTS (Dell Precission Tower 3620)