How to add a new type of virtio back-end driver in libvirt(or Virt-Manager)?

Question

I've made a new back-end driver for QEMU-KVM and I'd like it to be loaded for the guest OS. I'm using Virt-Manager to launch QEMU-KVM but I can't make my back-end driver loaded and ready to be used by guest OS.

I've tried to add the following item in DOMXML for the guest OS.

<controller type='virtio-mydevice' index='0'>
</controller>

But the virsh doesn't accept the item by telling the following error.

error: internal error Unknown controller type 'virtio-mydevice'

Is there any guide-line to meet this purpose?

Answer 1

I've just got the answer myself. Once you've added a new virtio back-end driver, the next thing you have to do is to add an item in QEMU option by editing qemu-option.hx. You can add your own QEMU option to load the virtio back-end driver, and virsh recognize the option once you add an option in qemu-option.hx, make and install the QEMU again.