A number of distributions (most importantly for me - Debian) use the
initrd as initramfs facility. I assumed that the passing of the data
block would be independent of ram disks seeing as not using a ram
disk was one of the major reasons for initramfs, but it seems that
you need CONFIG_BLK_DEV_INITRD=y which depends on
CONFIG_BLK_DEV_RAM=y
Would a patch separating out the init image handling from the initrd
handling be welcome and if so should the resulting init image code
be dependant on a CONFIG variable or always on (like initramfs is now)
The only reference to this I found in the archives was:
http://www.uwsg.indiana.edu/hypermail/linux/kernel/0508.1/0097.html