Goal

https://issues.redhat.com/browse/RHEL-114003 introduced the "host-model" mode for Hyper-V Enlightenments.

This feature is implemented in a way that doesn't allow explicitly enabling/disabling features while using the new host-model hyper-v mode.

This is based on the code here:

• here, Parser skips child elements for host-model:  if (mode == VIR_DOMAIN_HYPERV_MODE_PASSTHROUGH || mode == VIR_DOMAIN_HYPERV_MODE_HOST_MODEL) return 0;
• here, unconditionally sets every supported feature to ON: vm->def->hyperv.features[i] = VIR_TRISTATE_SWITCH_ON

This was intended to be consumed by KubeVirt in a way that we will always set "host-model" instead of "custom", so that the guest would pick up all available models on the host while still being able to explicitly enable/disable features - just like CPU host-model.

In Kubevirt, we wish to avoid exposing another "mode" in our APIs in order to help customers/users migrate to the new mode. A new API will make the delivery of this feature much slower and more complicated while unnecessarily complexing our APIs.

• As a user, I want to be able to set "host-model" mode for hyper-v and be able to enable/disable features explicitly.

Ideally, this should be backported to a version easily consumable by KubeVirt.

Acceptance criteria

• Verify that it's possible to set "host-model" mode for hyper-v and be able to enable/disable features explicitly.