initramfs-kernel
kernel runs /init.
/init is a script which sets INITRAMFS=1 and then execs /sbin/init.
/sbin/init is ELF comes from procd package. What it does:
- early:
- mount /proc, /sysfs, and create /dev nodes, create /tmp subdirs etc
- set PATH
- kmodloader in subprocess
- preinit
- plugd in subprocess (seem to deal with firmware)
- /etc/preinit in subprocess
- when /etc/preinit is done then it execs and replaces itself with the "real" /sbin/procd