Re: [PATCH v2] kbuild: fix UNUSED_KSYMS_WHITELIST for Clang LTO

[Sedat Dilek]

On Sat, Feb 27, 2021 at 7:55 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> On Fri, Feb 26, 2021 at 6:26 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
> >
> > On Fri, Feb 26, 2021 at 7:26 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
> > >
> > > Commit fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
> > > does not work as expected if the .config file has already specified
> > > CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling
> > > CONFIG_LTO_CLANG.
> > >
> > > So, the user-supplied whitelist and LTO-specific white list must be
> > > independent of each other.
> > >
> > > I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO
> > > handle whitelists in the same way.
> > >
> > > Fixes: fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
> > > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> > > ---
> > >
> > > Changes in v2:
> > >   - Rebase on top of Arnd's patch:
> > >     https://lore.kernel.org/lkml/20210225143456.3829513-1-arnd@xxxxxxxxxx/
> > >
> > >  init/Kconfig                    |  1 -
> > >  scripts/gen_autoksyms.sh        | 35 ++++++++++++++++++++++++---------
> > >  scripts/lto-used-symbollist.txt |  6 ------
> >
> > People who want to use their own "white-listed" (allow-listed)
> > symbollist-file can do that via
> > CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list".
> > Correct?
> >
> > Why do you delete the default "scripts/lto-used-symbollist.txt" file
> > and remove the default in the appropriate Kconfig for people who want
> > to enable Clang-(Thin)LTO?
> > These people should now use
> > CONFIG_UNUSED_KSYMS_WHITELIST="scripts/lto-used-symbollist.txt"?
> > But again - the file was deleted with your patch.
> > Do I miss something?
>
> I think so.
>
> I moved those symbols to scripts/gen_autoksyms.sh
>

OK, I have overseen hat.

- Sedat -