Lost of log file during block migration

    Hello, i've discovered that during live block migration
log file is copied(or created on destination) but it actually empty.
When regular(cold) migration is called log file migrates successfully.
I'm working on nova project in openstack and i've tried to fix it by adding
simple scp from source to destination, but log file is owned by libvirt-qemu user
and i cannot do that from regular user created by openstack.
Could explain how can i migrate logs safely?