Re: [PATCH] selftests/bpf: Fix check in global_data_init.

[Andrii Nakryiko]

On Thu, Sep 3, 2020 at 11:02 AM Hao Luo <haoluo@xxxxxxxxxx> wrote:
>
> The returned value of bpf_object__open_file() should be checked with
> IS_ERR() rather than NULL. This fix makes test_progs not crash when
> test_global_data.o is not present.
>
> Signed-off-by: Hao Luo <haoluo@xxxxxxxxxx>
> ---
>  tools/testing/selftests/bpf/prog_tests/global_data_init.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/global_data_init.c b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
> index 3bdaa5a40744..1ece86d5c519 100644
> --- a/tools/testing/selftests/bpf/prog_tests/global_data_init.c
> +++ b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
> @@ -12,7 +12,7 @@ void test_global_data_init(void)
>         size_t sz;
>
>         obj = bpf_object__open_file(file, NULL);
> -       if (CHECK_FAIL(!obj))
> +       if (CHECK_FAIL(IS_ERR(obj)))

Can you please use libbpf_get_error(obj) instead to set a good example
or not relying on kernel internal macros?

>                 return;
>
>         map = bpf_object__find_map_by_name(obj, "test_glo.rodata");
> --
> 2.28.0.402.g5ffc5be6b7-goog
>