QA:Testcase Virtualization KVM PCI Device Assignment assign using libvirt

Description

This case verifies that a PCI device can be assigned to a KVM guest and used successfully in the guest.

How to test

1. Edit an existing guest's configuration using virsh edit
2. In the devices section add a hostdev element describing the device using its PCI address

   <hostdev mode='subsystem' type='pci' managed='yes'>

   <source>

   <address bus='0x00' slot='0x19' function='0x00'/>

   </source>

   </hostdev>

3. Start the guest using virsh start
4. Try using the device in the guest - e.g. if it is a NIC, bring it up and ping a remote host
5. Shut down the guest
6. Re-attach the device in the host using virsh reattach (see 499561
7. Check that the device can be used in the host again

Expected Results

1. The guest should start without any errors
2. The device should be usable within the guest
3. When the guest has been shut down, the device should be usable in the host