(aarch64) KVM Guest NIC Hotplug Failure With romfile Error

When attaching a network device to a running KVM guest on an Arm platform, using the virsh attach-device command, the action can fail with the error:

failed to find romfile "efi-virtio.rom"

The efi-virtio.rom error is caused by virsh attach-device generating a <rom/> element in the configuration without setting bar="off", which QEMU can't resolve on this platform. Use the --rom bar=off option when you attach a network device using virsh attach-device, for example:

virsh attach-interface vm_name --type bridge --source virbr0 --model virtio --mac 52:54:00:96:82:11 --config --rom bar=off

Note:

This issue is specific to the QEMU version 10 and Libvirt version 12 Oracle Linux KVM stack.

(Bug 39018293)