Running legacy Windows versions

Legacy Windows versions like Windows XP or Windows Server 2003 are unable to boot on KubeVirt out of the box. This is due to the combination of the Q35 machine-type and a 64-Bit PCI hole reported to the guest, that is not supported by these operating systems.

To run legacy Windows versions on KubeVirt, reporting of the 64-Bit PCI hole needs to be disabled. This can be achieved by adding the kubevirt.io/disablePCIHole64 annotation with a value of true to a VirtualMachineInstance's annotations.

Example

With this VirtualMachine definition a legacy Windows guest is able to boot:

apiVersion: kubevirt.io/v1
kind: VirtualMachine
metadata:
  name: xp
spec:
  runStrategy: Always
  template:
    metadata:
      annotations:
        kubevirt.io/disablePCIHole64: "true"
    spec:
      domain:
        devices: {}
        memory:
          guest: 512Mi
      terminationGracePeriodSeconds: 180
      volumes:
      - containerDisk:
          image: my/windowsxp:containerdisk
        name: xp-containerdisk-0