[Vol-users] failing to map address space for a dump/snapshot file created by libvirt command

Hi, everybody, I'm a new comer to volatility framework. At the same time, I am getting to work with libvirt library. I created a dump file named 'vm1_snapshot' by using libvirt command like 'virsh save domain'. In the domain ran the WinXPSP3x86. However, when I used 'python vol.py -f ~/vm1_snapshot --profile=WinXPSP3x86 pslist', the result showed as 'No suitable address space mapping found‍'. How could this happen? Is there anything wrong with the way the snapshot file was created? I hope some guy can do me a favor. ‍