Re: Question regarding kernel policy: Why ext2 as module?

[Andree Leidenfrost <aleidenf@bigpond.net.au>]

Hi Sven

First of all thanks a lot for your response!

On Sun, 2004-07-18 at 19:32, Sven Luther wrote: 
> On Sun, Jul 18, 2004 at 07:05:20PM +1000, Andree Leidenfrost wrote:
> [most of my original posting removed]
> > 
> > I've looked into using a bare-bones cramfs initrd image that would only
> > load the ext2 module, mount the actual image via the loop device and do
> > a pivot_root to that. But apart from the fact that it would require
> > substantial and hard to justify changes upstream, I've really hit a
> > brickwall because cramfs only supports files < 16MB and my image is
> > substantially larger (~ 42MB).
> 
> Could it be possible to boot into a minimal initrd, as one generated by
> mkinitrd for example, and then use this to mount the larger ramdisk into
> one of the /dev/ram devices or something, and then pivot_root into this ? 

The chief problem seems to be accessing the image for the larger
ramdisk: If I want to mount it, it needs to be accessible as a file by
mount. Therefore it needs to be part of the initial (cramfs) initrd
image. This in turn is where I have a problem because cramfs only
supports files up to 16MB. Maybe I'm overlooking something very obvious
here...

> This should be the same kind of stuff that is already done with the
> initrd kernels, except you would need to add some script hook to load
> the ramdisk.

I've looked at the initrd image that comes with the 2.6.6-k7 kernel.
What linuxrc seems to be doing is resetting the root filesystem to
what's configured in the kernel. I can't see any use of a secondary
ramdisk. Also, I've looked at Debian Installer a few months ago. That
also uses a ext2 initrd image If I'm not mistaken. Where would I be able
to see the use of a secondary ramdisk from within a primary initrd
image?

> Friendly,
> 
> Sven Luther

Best regards & thanks again
Andree

-- 
Andree Leidenfrost
Sydney - Australia