Re: [PATCH] default to n for GROUP_SCHED and FAIR_GROUP_SCHED

[Sam Ravnborg <sam@ravnborg.org>]

On Mon, May 05, 2008 at 07:15:01PM +0200, Ingo Molnar wrote:
> 
> * Parag Warudkar <parag.warudkar@gmail.com> wrote:
> 
> > sched-devel does not boot on my machine - stops right after PCI: Not 
> > using mmconfig.
> > 
> > Here is my config for sched-devel - I did a echo "n" | make oldconfig 
> > after copying over the previous config file BTW. Should I try 
> > disabling things in config? What's most likely to break boot? (Seems 
> > likes there are a lot of significant changes in there.)
> 
> every config is supposed to work, but in general you should pick the 
> defaults instead of saying 'n' to all questions. As long as every 
> question can be answered with an 'enter', this should work:
> 
>   make oldconfig < /dev/null
> 
> this non-interactive 'make oldconfig' will hang with the kconfig tool 
> looping infinitely if there's any numeric question that cannot be 
> answered via 'enter'.
> 
> This is a many years old kconfig bug that is frequently hacked around in 
> distro kernel packages but which has been ignored upstream - i've 
> attached Fedora's nonint_oldconfig patch from Dave Jones below. (maybe 
> Arjan wrote it originally?)

In latest kbuild.git I've added a new feature.

	make K=.config alldefconfig

would give you eaxtly what you request here.
K= is used to say where to locate the base-configuration.

The above will give you a configuration based on your old configuration
with all new options set to default values.

That could maybe be more intuitive but when you consider it you
could have your base config in many different places.
Like /boot/config-xxx, /proc/config.gz etc.
So allowing the user to specify the base config with K= seems
like an acceptable solution.

Current version in kbuild.git is broken with respect to make O=...
builds but that will be fixed in an hour or so.

redhat has the added possibility to list new symbols.
This is not yet included in mainline.
Not that it is difficult - I just need to decide where/how to do it.

	Sam