Description of problem:
Live migration of a domain with a PCI device hotplugged,it pops up error message:"error: POST operation failed: xend_post: error from xen daemon: (xend.err '/usr/lib64/xen/bin/xc_save 4 3 0 0 1 failed')" then the migration failed.
Look at the status of the guest,its status is paused.

Version-Release number of selected component (if applicable):
libvirt-0.8.2-15.el5
libvirt-python-0.8.2-15.el5
kernel-xen-2.6.18-225.el5
kernel-2.6.18-236.el5

How reproducible:
always

Steps to Reproduce:
1.# virsh start <domain>
2. Hotplug a PCI device to the domain;
   # virsh attach-device <domain> <device.xml>
cat device.xml
<disk type='file' device='disk'>
      <driver name='tap' type='aio'/>
      <source file='/root/test.img'/>
<target dev='xvdb' bus='xen'/>
</disk>
3. virsh migrate --live <domain> xen+ssh://host2
4. root.83.194's password: 
error: POST operation failed: xend_post: error from xen daemon: (xend.err '/usr/lib64/xen/bin/xc_save 4 3 0 0 1 failed')
5.Look at the status of the guest 
 Id Name                 State
----------------------------------
  4 xenpv                paused

Actual results:


Expected results:
The guest status should be running if it fails migration

Additional info: