[libvirt-users] virsh attach makes qcow2 format disk to raw format

Hi all I have a problem when I use `virsh attach` to attach a qcow2 disk to vm without argument --subdirver=qcow2 and this makes the qcow2 disk become a raw format disk, and the data in this disk is missing in guest os and also I have used guestmout to confirm this, the same result. Is there any way to let me find back the data in this disk ? the version of libvirt and kvm is : Compiled against library: libvir 0.9.8 Using library: libvir 0.9.8 Using API: QEMU 0.9.8 Running hypervisor: QEMU 1.0.0 Best Regards Li Yuezhou