Re: [Q] pivot_root and initrd

["H. Peter Anvin" <hpa@zytor.com>]

Followup to:  <ujkB7.3878$1%5.659642574@newssvr17.news.prodigy.com>
By author:    davidsen@tmr.com (bill davidsen)
In newsgroup: linux.dev.kernel
> 
> I wasn't really asking about changing root after the system is up, the
> part needed is the uncompressing of the filesystem into a ramdisk root f/s
> or some such. After that it's pretty much open to any of several techniques.
> 
> Getting the modules loaded to support the root f/s and run a little rc
> file to get things going is the bootstrap operation, and that's where
> initrd is vital. You really don't want to build a kernel for every
> machine if you have more than a few! One kernel and a few config and
> initrd files is vastly easier.
> 
> What replaces the initial step?
> 

We will definitely have initrd or initramfs to do this (initramfs is
using the initrd protocol to populate a ramfs from a tar/cpio image.)
However, when it comes up, it will be the root as far as the kernel is
concerned, and run /sbin/init (unless overridden on the kernel command
line, of course) like any other boot.  None of this change_root and
/linuxrc special casing garbage.

	-hpa
-- 
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