Re: [PATCH 5.4 007/102] libbpf: Fix call relocation offset calculation bug

[Sasha Levin]

On Fri, Jan 24, 2020 at 07:13:27PM +0530, Naresh Kamboju wrote:
> <trim>
> > Fixes: 48cca7e44f9f ("libbpf: add support for bpf_call")
> > Reported-by: Alexei Starovoitov <ast@xxxxxxxxxx>
> > Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
> > Acked-by: Yonghong Song <yhs@xxxxxx>
> > Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
> > Link: https://lore.kernel.org/bpf/20191119224447.3781271-1-andriin@xxxxxx
> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >
> > ---
> >  tools/lib/bpf/libbpf.c                             |    8 ++++++--
> >  tools/testing/selftests/bpf/progs/test_btf_haskv.c |    4 ++--
> >  tools/testing/selftests/bpf/progs/test_btf_newkv.c |    4 ++--
> >  tools/testing/selftests/bpf/progs/test_btf_nokv.c  |    4 ++--
> >  4 files changed, 12 insertions(+), 8 deletions(-)
> >
> > --- a/tools/lib/bpf/libbpf.c
> > +++ b/tools/lib/bpf/libbpf.c
> > @@ -1791,9 +1791,13 @@ bpf_program__collect_reloc(struct bpf_pr
> >                                 pr_warning("incorrect bpf_call opcode\n");
> >                                 return -LIBBPF_ERRNO__RELOC;
> >                         }
> > +                       if (sym.st_value % 8) {
> > +                               pr_warn("bad call relo offset: %lu\n", sym.st_value);
>
> Perf build failed on stable-rc 5.4 branch for arm, arm64, x86_64 and i386.
>
> libbpf.c: In function 'bpf_program__collect_reloc':
> libbpf.c:1795:5: error: implicit declaration of function 'pr_warn';
> did you mean 'pr_warning'? [-Werror=implicit-function-declaration]
>     pr_warn("bad call relo offset: %lu\n", sym.st_value);
>     ^~~~~~~
>     pr_warning
> libbpf.c:1795:5: error: nested extern declaration of 'pr_warn'
> [-Werror=nested-externs]
> Makefile:653: arch/arm64/Makefile: No such file or directory
> cc1: all warnings being treated as errors
>
> build links,
> https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.4/DISTRO=lkft,MACHINE=hikey,label=docker-lkft/69/consoleText
> https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.4/DISTRO=lkft,MACHINE=intel-corei7-64,label=docker-lkft/69/consoleText

Oh, I realized I'm not testing libbpf. I'll drop this patch for now.

--
Thanks,
Sasha