Description of problem:

QEMU/KVM live migration on non-shared storage using --copy-storage-all fails with error message "error: unable to set user and group to '(UID):(GID)' on '/PATH/TO/IMAGE': No such file or directory" if the image file is not created
in advance on the destination host. In case an empty image with identical path is created manually using "qemu-img create", the migration succeeds. Note however, simply creating an empty file with touch(1) is not enough, it 
needs to be a qemu supported image file (I've tested with qcow2).

I think this is unexpected (undocumented at least) behavior --libvirt (or qemu?) should create an empty image if it does not exists already. OTOH, if it does, maybe it should even warn the user before overwriting it?

Version-Release number of selected component (if applicable):

libvirt 0.9.4 (from Debian Experimental)
qemu-kvm 0.15 (from Debian Experimental)

How reproducible:

Always.

Steps to Reproduce:
1. migrate --live --verbose --copy-storage-all DOMAIN qemu+ssh://DESTHOST/system
  
Actual results:

error: unable to set user and group to '107:107' on '/data/vm/ahlghe-test2.qcow2': No such file or directory

Expected results:

Disk image created, it's content copied and virtual machine migrated.

Additional info: