Description of problem:
Fail to convert a preallocated xen vm locally. Convert a sparse vm is OK.


Version-Release number of selected component (if applicable):
virt-v2v-0.7.1-4.el5
libguestfs-1.2.7-1.el5.13
zlib-1.2.3-3

How reproducible:
always

Steps to Reproduce:
1. In Kernel-xen, dump xml for a xen vm
 #virsh dumpxml xml  rhel4-32-min-2 > rhel4-32-min-2.xml

2. Shift from kernel-xen to kernel, convert the above vm locally
# virt-v2v -i libvirtxml rhel4-32-min-2.xml -os default -b breth0 
size (1572864000) < usage (1574404096) at /usr/lib/perl5/vendor_perl/5.8.8/Sys/VirtV2V/Connection/LibVirtXMLSource.pm line 157, <$qemuimg> line 4.

  
Actual results:
as steps mentioned

Expected results:
Convert locally vm successfully

Additional info:
# ll rhel4-32-hvm-min-2.img 
-rwxr-xr-x 1 root root 1572864000 May 30 14:44 rhel4-32-hvm-min-2.img

# ll -sh rhel4-32-hvm-min-2.img 
1.5G -rwxr-xr-x 1 root root 1.5G May 30 14:44 rhel4-32-hvm-min-2.img

# qemu-img info rhel4-32-hvm-min-2.img 
image: rhel4-32-hvm-min-2.img
file format: raw
virtual size: 1.5G (1572864000 bytes)
disk size: 1.5G


# cat rhel4-32-min-2.xml
<domain type='xen'>
  <name>rhel4-32-hvm-min-2</name>
  <memory>524288</memory>
  <currentMemory>524288</currentMemory>
  <vcpu>1</vcpu>
  <os>
    <type arch='x86_64' machine='xenfv'>hvm</type>
    <loader>/usr/lib/xen/boot/hvmloader</loader>
    <boot dev='hd'/>
..
    <disk type='file' device='disk'>
      <driver name='file'/>
      <source file='/var/lib/libvirt/images/rhel4-32-hvm-min-2.img'/>
      <target dev='hda' bus='ide'/>
    </disk>
    <disk type='block' device='cdrom'>
      <driver name='phy'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
    </disk>
...