Re: [PATCHv2] kconfig: add some Kconfig env variables to make help

From: Masahiro Yamada <masahiroy@kernel.org>
To: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCHv2] kconfig: add some Kconfig env variables to make help
Date: Fri, 1 Mar 2024 00:35:18 +0900	[thread overview]
Message-ID: <CAK7LNAS-mOxY884pLEMwWaX+wgzXdc6+=vqN=wfHBekuKL5ryA@mail.gmail.com> (raw)
In-Reply-To: <20240229034739.GN11972@google.com>

On Thu, Feb 29, 2024 at 12:47 PM Sergey Senozhatsky
<senozhatsky@chromium.org> wrote:
>
> On (24/02/29 12:36), Masahiro Yamada wrote:
> > > On (24/02/29 11:03), Masahiro Yamada wrote:
> > > > > > > > +++ b/scripts/kconfig/Makefile
> [..]
> > > > > > > > +       @echo  ''
> > > > > > > > +       @echo  'Configuration environment variables:'
> > > > > > > > +       @echo  '  KCONFIG_WERROR                 - Turn some Kconfig warnings into error conditions'
> > > > > > > > +       @echo  '  KCONFIG_WARN_UNKNOWN_SYMBOLS   - Make Kconfig warn about all unrecognized config symbols'
> > > > > > > >
> > > > > > > >  # ===========================================================================
> > > > > > > >  # object files used by all kconfig flavours
> > > > > > > > --
> > > > > > > > 2.44.0.rc0.258.g7320e95886-goog
> > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > > > Why only two, while Kconfig supports more env variables?
> > > > > >
> > > > > > Right.  I wanted to add only those that we use (and familiar with) for
> > > > > > starters.  I'm not familiar with things like KCONFIG_PROBABILITY, for
> > > > > > instance, and not sure how to document it (its Documentation/kbuild/kconfig.rst
> > > > > > description is pretty lengthy).
> > > > >
> > > > > Masahiro, any opinion?
> > > >
> > > >
> > > > I do not need this patch.
> > >
> > > Do you agree that putting kconfig env knobs into help makes sense
> > > in general?  Especially those add valuable sanity checks.
> >
> > I cannot accept the attitude:
>
> This is entirely wrong interpretation.
>
> >   "I am interested only in these. I do not care about the rest,
>
> It's "I *do NOT know* what the rest do".  I cannot document something
> that I have no knowledge of, can I?  So as a reasonable start I added
> only those that I'm familiar with (and I have explicitly stated that
> in previous emails), and I disagree with the "bad attitude" label.

You were aware of:

 - several env variables are listed in the document
 - your patch would introduce a new "inconsistency"
 - somebody else would need to make efforts to solve it

> > This should be all or nothing.
> >
> > I do not think all the env variables can be summarized
> > to fit in help.
>
> So the rational for that was that people run "make help" and find
> out about new build targets, for instance, but there is no way for
> people to find out about new Kconfig features (and yes, we are talking
> "new features" here) that are controlled by env variables.  We need
> to do something about it, don't you agree?

Disagree.

I maintain the entire Kconfig, not like you only caring about
a particular feature.

If you add only two in help, I have no idea about
what it will look like in the end.
I am not convinced that it will be in good shape.
So, it is reasonable for me to reject it.

-- 
Best Regards
Masahiro Yamada