Re: Kernel setup() and initrd problems

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

Followup to:  <Pine.LNX.4.44.0303131051160.7342-100000@chaos.physics.uiowa.edu>
By author:    Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
In newsgroup: linux.dev.kernel
> 
> I think whoever came up with that just got the idea of pivot_root wrong. 
> The idea was to get rid of the initrd special case. It should be possible 
> to do the following, though I didn't work out the details: 
> 
> Tell the kernel that our root dev is /dev/ram and give it an initrd which 
> isn't really a classical initrd (with /linuxrc on it), but instead has a 
> /sbin/init which is similar to the linuxrc above.
> 

It *is* possible, but you need to pass "root=/dev/ram0" to the kernel,
for backwards compatibility reasons.  That will incidentally make it
run /sbin/init, not /linuxrc, unless you pass init=/linuxrc as well.

See SuperRescue for an example of working use of pivot_root.

	-hpa
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