skipping non-regular file "mnt/lib/udev/devices/console"
skipping non-regular file "mnt/lib/udev/devices/kmem"
skipping non-regular file "mnt/lib/udev/devices/loop0"
skipping non-regular file "mnt/lib/udev/devices/null"
skipping non-regular file "mnt/lib/udev/devices/ppp"
skipping non-regular file "mnt/lib/udev/devices/net/tu

Solution for skipping non-regular file

You need the -D switch which is a hybrid of --specials and --devices so all special and device files will be copied as well.