[ILUG] Kernel configuration strangeness

[Niall O Broin]

On Friday 30 April 2004, tim at birdsnest.maths.tcd.ie (Timothy Murphy)
wrote:

>I was quite surprised when I did this (with kernel -2.6.6-rc2)
>that I actually got exactly the same 3 .config files from
>make distclean
>make oldconfig
>cp .config oldconfig
>make distclean
>make xconfig
>cp .config xconfig
>make distclean
>make menuconfig
>cp .config menuconfig
>
>I'd actually expected 3 different config files
>but in fact they were identical.
>
>[tim at martha linux-2.6.6-rc2]$ ls -ls *config
>28 -rw-rw-r--  1 tim tim 26676 Apr 30 15:46 menuconfig
>28 -rw-rw-r--  1 tim tim 26676 Apr 30 15:41 oldconfig
>28 -rw-rw-r--  1 tim tim 26676 Apr 30 15:44 xconfig


Why would you be surprised? I'd expect a make *config to produce the
same output

[root at Server3 linux-2.4.21-9.0.1.EL]# for config in old menu x
> do make distclean
> cp configs/kernel-2.4.21-athlon.config .config
> make ${config}config
> cp .config CONFIG.$config
> done

LOTS of uninteresting output skipped . . .

[root at Server3 linux-2.4.21-9.0.1.EL]# ls -l CONFIG.*
-rw-r--r--    1 root     root        41054 Apr 30 15:56 CONFIG.menu
-rw-r--r--    1 root     root        42298 Apr 30 15:55 CONFIG.old
-rw-r--r--    1 root     root        40995 Apr 30 15:57 CONFIG.x

I also did the same test, WITHOUT copying in the sample config file
first, and again I got three different files. (Didn't keep the previous
ones to compare. .menu and .old were the same lengths, but .x WITHOUT
using the sample files was much smaller). I find this strange, to say
the least.

I also tried this with a kernel.org 2.6.5 kernel tree and got similar
results to Tim.



Niall