I have tried to set this in my XML-File:
https://specs.openstack.org/openstack/nova-specs/specs/train/approved/allow-secure-boot-for-qemu-kvm-guests.html
<os firmware='efi'>
<type arch='x86_64' machine='pc-q35-5.1'>hvm</type>
<loader secure='yes'/>
</os>
But now I am missing the template nvram file: /usr/share/qemu/edk2-i386-vars.fd
Probably configured through: /usr/share/qemu/firmware/50-edk2-x86_64-secure.json
Using the existing nvram file of the VM just turns all cores asigned to the VM to 100% and a black screen.
Nothing special in the log.