Description of problem:
Failed to pci hotplug/passthrough to guest in selinux enabled

Version-Release number of selected component (if applicable):
- 2.6.18-256.el5
- kvm-83-230.el5
- libvirt-0.8.2-18.el5

How reproducible:
always

Steps to Reproduce:
1. Enable vt-d on the host
2. # getenforce 
Enforcing
3. # virsh nodedev-list --tree
computer
 |
  +- pci_8086_10de
  |   |
  |   +- net_00_25_64_a7_1f_4d
  |     
  +- pci_8086_244e
  +- pci_8086_2822
  |   |
........
4. # virsh nodedev-dumpxml pci_8086_10de
<device>
  <name>pci_8086_10de</name>
  <parent>computer</parent>
  <driver>
    <name>e1000e</name>
  </driver>
  <capability type='pci'>
    <domain>0</domain>
    <bus>0</bus>
    <slot>25</slot>
    <function>0</function>
    <product id='0x10de'>82567LM-3 Gigabit Network Connection</product>
    <vendor id='0x8086'>Intel Corporation</vendor>
  </capability>
</device>
5. # cat nodedev.xml 
<hostdev mode='subsystem' type='pci' managed='yes'>
 <source>
  <address bus='0' slot='0x19' function='0'/>
 </source>
</hostdev>
6. Start a guest
# virsh start rhel61
Domain rhel61 started
7. # virsh attach-device rhel61 nodedev.xml 
error: Failed to attach device from nodedev.xml
error: operation failed: parsing pci_add reply failed: Failed to assign device
failed to add host=00:19.0
8. OR change to do pci passthrough, firstly shutdown the guest, then add nodedev.xml info into guest config file and try to start the guest

  
Actual results:
7. Failed to hotplug pci device to guest
8. Failed to boot up the guest when passthrough the pci device to guest

Expected results:
7. pass
8. pass

Additional info:
If change selinux to permissive, both the operation could be pass.