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

Sasha Levin
2020-01-24T15:18:22Z

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@kernel.org>
>> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
>> Acked-by: Yonghong Song <yhs@fb.com>
>> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
>> Link: https://lore.kernel.org/bpf/20191119224447.3781271-1-andriin@fb.com
>> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>>
>> ---
>> 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