Given nova.virt.libvirt.utils.create_cow_image which is calling qemu-img create with a backing file but not specifying the backing file format, I'd consider nova affected by this issue:
https://github.com/openstack/nova/blob/master/nova/virt/libvirt/utils.py#L75
Given nova.virt. libvirt. utils.create_ cow_image which is calling qemu-img create with a backing file but not specifying the backing file format, I'd consider nova affected by this issue:
https:/ /github. com/openstack/ nova/blob/ master/ nova/virt/ libvirt/ utils.py# L75