if [ "${on_disk/vmlinu}" != "$on_disk" ]; then
on_disk_version="`get_image_linux "$on_disk" | strings | grep 'Linux version' | head -n1`"
[ -z "$on_disk_version" ] || break
if [ "${on_disk/vmlinu}" != "$on_disk" ]; then
on_disk_version="`get_image_linux "$on_disk" | strings | grep 'Linux version' | head -n1`"
[ -z "$on_disk_version" ] || break