[Buildroot] buildroot with SquashFS root file system

[Michael S. Zick <minimod@morethan.org>]

On Thu December 8 2011, Emmanuel BOUAZIZ wrote:
> 
> On 12/08/2011 11:48 AM, Peter Korsgaard wrote:
> 
> >  Emmanuel> The only remaining problem is that the whole filesystem is
> >  Emmanuel> read-only despite the 'rw' including /var and /tmp.
> > 
> > That's because you're using squashfs. Squashfs is a readonly
> > filesystem. Either move to initramfs or use ext2 in your initrd.
> > 
> 
> > /tmp should be a tmpfs though (check /etc/fstab), and most of /var
> > symlinks to /tmp/.
> > 
> 
> Oh that's rigth, it's writable, I mixed with another directory that I wanted to write to (/usr/local). I mounted it as
> tmpfs too and everything's fine now. Thanks a lot for your help :)
> 
> Well, I'll switch back to initramfs anyway since it's less tricky.
>

You do not have to put your entire run-time file system in the initramfs,
only what you need to establish the full run-time file system.
I.E: Your full run-time file system can remain as a squashfs file.
You just have to provide the "init" scripting to get it loaded and
mounted while in the early user space of the initramfs.

See: EarlyUserSpace in the kernel documentation tree;
and maybe look at how some "LiveCD" systems handle the setup.

Mike 
> regards,