Differences between two xml files one from a 12.04 host installation
and one from a 14.04 server host installation.

doug@s15:/etc/libvirt/qemu$ sudo diff desk_tt.xml.1204 desk_tt.xml.1404

11,13c11,13
<   <memory>8388608</memory>
<   <currentMemory>8388608</currentMemory>
<   <vcpu>4</vcpu>
---
>   <memory unit='KiB'>8388608</memory>
>   <currentMemory unit='KiB'>8388608</currentMemory>
>   <vcpu placement='static'>4</vcpu>
15c15
<     <type arch='x86_64' machine='pc-1.0'>hvm</type>
---
>     <type arch='x86_64' machine='pc-i440fx-1.7'>hvm</type>
28c28
<     <emulator>/usr/bin/kvm</emulator>
---
>     <emulator>/usr/bin/kvm-spice</emulator>
39c39
<       <address type='drive' controller='0' bus='1' unit='0'/>
---
>       <address type='drive' controller='0' bus='1' target='0' unit='0'/>
43a44,47
>     <controller type='usb' index='0'>
>       <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
>     </controller>
>     <controller type='pci' index='0' model='pci-root'/>
56a61
>     <input type='keyboard' bus='ps2'/>