Re: [PATCH] modpost: propagate W=1 build option to modpost

[Nick Desaulniers]

On Tue, Jun 6, 2023 at 10:21 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> On Wed, Jun 7, 2023 at 1:56 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote:
> >
> > On Tue, Jun 6, 2023 at 2:42 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
> > >
> > > "No build warning" is a strong requirement these days, so you must fix
> > > all issues before enabling a new warning flag.
> > >
> > > We often add a new warning to W=1 first so that the kbuild test robot
> > > blocks new breakages.
> > >
> > > This commit allows modpost to show extra warnings only when W=1
> > > (or KBUILD_EXTRA_WARN=1) is given.
> > >
> > > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> >
> > Patch seems fine, but without anyone reading extra_warn, I'm curious
> > what new extra warnings you had in mind were?
>
>
> This one.
>
> https://lore.kernel.org/linux-kbuild/CAK7LNAR0uMvf+k7LPXtMjigKFPeNu5m5EhAkvk2RVRHkdjdbdg@xxxxxxxxxxxxxx/T/#m0f41f2c8fe843133ce8100088443491a51d496af

Yeah, ok so we'll guard that warning on this extra_warn then? Seems fine.

Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>

>
>
> > > ---
> > >
> > >  scripts/Makefile.modpost | 1 +
> > >  scripts/mod/modpost.c    | 7 ++++++-
> > >  2 files changed, 7 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
> > > index 0980c58d8afc..074e27c0c140 100644
> > > --- a/scripts/Makefile.modpost
> > > +++ b/scripts/Makefile.modpost
> > > @@ -47,6 +47,7 @@ modpost-args =                                                                                \
> > >         $(if $(KBUILD_MODPOST_WARN),-w)                                                 \
> > >         $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS))                                     \
> > >         $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N)       \
> > > +       $(if $(findstring 1, $(KBUILD_EXTRA_WARN)),-W)                                  \
> > >         -o $@
> > >
> > >  modpost-deps := $(MODPOST)
> > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> > > index d10f5bdcb753..3ea5eb2b1029 100644
> > > --- a/scripts/mod/modpost.c
> > > +++ b/scripts/mod/modpost.c
> > > @@ -42,6 +42,8 @@ static bool allow_missing_ns_imports;
> > >
> > >  static bool error_occurred;
> > >
> > > +static bool extra_warn;
> > > +
> > >  /*
> > >   * Cut off the warnings when there are too many. This typically occurs when
> > >   * vmlinux is missing. ('make modules' without building vmlinux.)
> > > @@ -2199,7 +2201,7 @@ int main(int argc, char **argv)
> > >         LIST_HEAD(dump_lists);
> > >         struct dump_list *dl, *dl2;
> > >
> > > -       while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
> > > +       while ((opt = getopt(argc, argv, "ei:mnT:o:aWwENd:")) != -1) {
> > >                 switch (opt) {
> > >                 case 'e':
> > >                         external_module = true;
> > > @@ -2224,6 +2226,9 @@ int main(int argc, char **argv)
> > >                 case 'T':
> > >                         files_source = optarg;
> > >                         break;
> > > +               case 'W':
> > > +                       extra_warn = true;
> > > +                       break;
> > >                 case 'w':
> > >                         warn_unresolved = true;
> > >                         break;
> > > --
> > > 2.39.2
> > >
> >
> >
> > --
> > Thanks,
> > ~Nick Desaulniers
>
>
>
> --
> Best Regards
> Masahiro Yamada



-- 
Thanks,
~Nick Desaulniers