Re: [PATCH] scripts/kconfig/merge_config: don't redefine 'y' to 'm'

[Darren Hart]

On Tue, Nov 06, 2018 at 02:57:40PM +0100, Anders Roxell wrote:
> On Mon, 5 Nov 2018 at 09:35, Masahiro Yamada
> <yamada.masahiro@xxxxxxxxxxxxx> wrote:
> >
> > Hi Anders,
> >
> > On Fri, Nov 2, 2018 at 8:41 PM Anders Roxell <anders.roxell@xxxxxxxxxx> wrote:
> > >
> > > In today's merge_config.sh the order of the config fragment files dictates
> > > the output of a config option. With this approach we will get different
> > > .config files depending on the order of the config fragment files.
> > > Adding a switch to add precedence for builtin over modules, this will
> > > make the .config file the same
> > >
> > > Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
> > > Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
> > > ---
> >
> > I think this patch makes sense.
> >
> > Just in case, could you please provide me the context of the discussion?
> 
> For instance we don't want to force X86 from DRM=y to DRM=m, when
> enabling selftest, that would surely break somebody's setup and you also
> don't want to force ARM64 from DRM=m to DRM=y, that seems
> unnecessary for a big subsystem like DRM.
> 
> >
> > Does the real problem exist in the kernel tree,
> 
> Not that I'm aware about.
> 
> Cheers,
> Anders
> 
> > or for local fragment files?

This is really about ordering of fragment files and not "making a symbol
'less'", I think were Arnd's words.

So, doing something like:

$ make arm64-selftest.config drm.config

where arm64-selftest.config defines DRM=y and drm.config defines DRM=m, the
result should be "DRM=y".

So the first step is to make merge_config.sh support it. A follow up step would
be to integrate this into the kernel Makefile system if we determine this is the
correct behavior, or to provide a parameter if we don't want to change the
default behavior.


-- 
Darren Hart
VMware Open Source Technology Center