Originally Posted By: mlord
the initial partitioning is still done by the firmware (?) prior to the /sbin/init script being run

This is /linuxrc in the initrd.
Code:
RAMDISK: ext2 filesystem found at block 0
RAMDISK: Loading 320 blocks [1 disk] into ram disk... done.
VFS: Mounted root (ext2 filesystem).
empeg-pump v0.03 (19980601)
Press Ctrl-A to enter pump...VFS: Mounted root (ext2 filesystem) readonly.
change_root: old root has d_count=1
Trying to unmount old root ... okay

By "pressing Ctrl-A" (i.e. sending \x01 down the serial port) the upgrader stops /linuxrc from mounting the disk-based root partition on / and exiting to {/dev/hda5}/sbin/init -- and, instead, causes it to enter "upgrader mode", where the commands available include partitioning a drive, and filling a partition from a gzipped filesystem image down the serial port.

Peter