From: Olaf Hering <olh@suse.de>

initramfs can not be used in current 2.6 kernels, the files will never be
executed because prepare_namespace doesn't care about them.  The only way to
workaround that limitation is a root=0:0 cmdline option to force rootfs as
root filesystem.  This will break further booting because rootfs is not the
final root filesystem.

This patch checks for the presence of /init which comes from the cpio archive
(and thats the only way to store files into the rootfs).  This binary/script
has to do all the work of prepare_namespace().