<domain>
  <devices>
    <hostdev mode="subsystem" type="pci" managed="yes">
      <boot order="1"/>
      <rom bar="on" file="/etc/fake/boot.bin"/>
      <source>
        <address domain="0x0001" bus="0x02" slot="0x03" function="0x4"/>
      </source>
    </hostdev>
  </devices>
</domain>