For dealing with cpio archives, just use pax. * http://netbsd.gw.com/cgi-bin/man-cgi?pax http://netbsd.gw.com/cgi-bin/man-cgi?pax * https://manpages.debian.or

For dealing with cpio archives, just use pax. * http://netbsd.gw.com/cgi-bin/man-cgi?pax http://netbsd.gw.com/cgi-bin/man-cgi?pax * https://manpages.debian.org/unstable/pax/pax.1.en.html https://manpages.debian.org/unstable/pax/pax.1.en.html * http://pubs.opengroup.org/onlinepubs/9699919799/ http://pubs.opengroup.org/onlinepubs/9699919799/ The answer to Why? is given in the kernel doco itself, in Documentation/filesystems/ramfs-rootfs-initramfs.txt .