Re: [PATCH] treewide: drop CONFIG_EMBEDDED

[Jesse T]

On Fri, Aug 18, 2023 at 7:44 PM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
>
> Hi Jesse,
>
> I replied to your comment a few days ago, but for some reason
> your email to me contains:
> Reply-To: 20230816055010.31534-1-rdunlap@xxxxxxxxxxxxx
> so it wasn't sent directly to you.

Sorry about that I messed up the email headers...
>
> My former reply is below.
>
> On 8/16/23 20:15, Randy Dunlap wrote:
> > Hi Jesse,
> >
> > On 8/16/23 15:45, Jesse Taube wrote:
> >> Hi, Randy
> >>
> >>> diff -- a/init/Kconfig b/init/Kconfig
> >>> --- a/init/Kconfig
> >>> +++ b/init/Kconfig
> >>> @@ -1790,14 +1790,6 @@ config DEBUG_RSEQ
> >>>
> >>>         If unsure, say N.
> >>>
> >>> -config EMBEDDED
> >>> -    bool "Embedded system"
> >>> -    select EXPERT
> >>> -    help
> >>> -      This option should be enabled if compiling the kernel for
> >>> -      an embedded system so certain expert options are available
> >>> -      for configuration.
> >>
> >> Wouldn't removing this break many out of tree configs?
> >
> > I'm not familiar with out-of-tree configs.
> > Do you have some examples of some that use CONFIG_EMBEDDED?
> > (not distros)

Buildroot has a few.
It won't immediately break Buildroot and Yocto as they have a set version,
but it could be confusing for anyone updating the kernel.

> >
> >> Should there be a warning here to update change it instead of removal?
> >
> > kconfig doesn't have a warning mechanism AFAIK.
> > Do you have an idea of how this would work?

No, unfortunately. As you said without a warning it would be overlooked so
a change would not be necessary.

A possible solution is to check in a header file with:

#ifdef CONFIG_EMBEDDED
#warning "CONFIG_EMBEDDED has changed to CONFIG_EXPERT"
#endif

Does anyone else have an opinion on this?
Since kconfig doesn't have a warning mechanism the patch seems fine as is.

Thanks,
Jesse Taube
> >
> > We could make a smaller change to init/Kconfig, like so:
> >
> >  config EMBEDDED
> > -     bool "Embedded system"
> > +     bool "Embedded system (DEPRECATED)"
> >       select EXPERT
> >       help
> > -       This option should be enabled if compiling the kernel for
> > -       an embedded system so certain expert options are available
> > -       for configuration.
> > +       This option is being removed after Linux 6.6.
> > +       Use EXPERT instead of EMBEDDED.
> >
> > but there is no way to produce a warning message. I.e., even with this
> > change, the message will probably be overlooked.
> >
> > ---
> > ~Randy
>
> --
> ~Randy