Re: [linux-next:master 6721/7715] arch/s390/kernel/vdso64/getcpu.c:8:5: warning: no previous prototype for function '__s390_vdso_getcpu'

[Souptick Joarder <jrdr.linux@gmail.com>]

On Wed, Nov 25, 2020 at 4:11 AM kernel test robot <lkp@intel.com> wrote:
>
> Hi Heiko,
>
> FYI, the error/warning still remains.
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   d9137320ac06f526fe3f9a3fdf07a3b14201068a
> commit: 80f06306240e0ad1c75116111be11950474dfda7 [6721/7715] s390/vdso: reimplement getcpu vdso syscall
> config: s390-randconfig-r015-20201124 (attached as .config)
> compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project df9ae5992889560a8f3c6760b54d5051b47c7bf5)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install s390 cross compiling tool for clang build
>         # apt-get install binutils-s390x-linux-gnu
>         # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=80f06306240e0ad1c75116111be11950474dfda7
>         git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>         git fetch --no-tags linux-next master
>         git checkout 80f06306240e0ad1c75116111be11950474dfda7
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> >> arch/s390/kernel/vdso64/getcpu.c:8:5: warning: no previous prototype for function '__s390_vdso_getcpu' [-Wmissing-prototypes]
>    int __s390_vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
>        ^
>    arch/s390/kernel/vdso64/getcpu.c:8:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>    int __s390_vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
>    ^
>    static
>    1 warning generated.

I think a declaration would be more appropriate.

>
> vim +/__s390_vdso_getcpu +8 arch/s390/kernel/vdso64/getcpu.c
>
>      7
>    > 8  int __s390_vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org