View source for Testcase USB Virtualization

=== Setup ===
* Host arch: x86_64, setup both x86_64 and i386 guests
* Power on host
* Start a virtual machine with default configuration

=== How to test ===
* Attach the USB device
* Run lsusb and determin which usb device you want guest to load
* Run virsh attach-device <domain> usb.xml
* You can find <domain> by running virsh list
* For example usb.xml is
  <hostdev mode='subsystem' type='usb' managed='yes'>
     <source>
       <product id='0x5567'/>
       <vendor id='0x0781'/>
     </source>
   </hostdev>