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From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Tue, 1 Dec 2020 17:38:17 -0800
Message-ID: <CAEf4BzY1Q7XZVMheN-e78HCO=M74frFM1d6h56-ChTNrDhNMUw@mail.gmail.com>
Subject: Re: [PATCH] tools/bpf: Return the appropriate error value
To:     =?UTF-8?B?5b2t5rWpKFJpY2hhcmQp?= <richard.peng@oppo.com>
Cc:     "ast@kernel.org" <ast@kernel.org>,
        "daniel@iogearbox.net" <daniel@iogearbox.net>,
        "bpf@vger.kernel.org" <bpf@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Mon, Nov 30, 2020 at 7:06 PM =E5=BD=AD=E6=B5=A9(Richard) <richard.peng@o=
ppo.com> wrote:
>
> Compile times error:
> "Error: failed to load BTF from /mnt/linux/vmlinux: No such file or direc=
tory".
> This file "/mnt/linux/vmlinux" actually exists, but only because CONFIG_D=
EBUG_INFO_BTF
> is not configured with this error.
>
> Signed-off-by: Peng Hao <richard.peng@oppo.com>
> ---
>  tools/lib/bpf/btf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> index 231b07203e3d..228f508fbd04 100644
> --- a/tools/lib/bpf/btf.c
> +++ b/tools/lib/bpf/btf.c
> @@ -865,7 +865,7 @@ struct btf *btf__parse_elf(const char *path, struct b=
tf_ext **btf_ext)
>         err =3D 0;
>
>         if (!btf_data) {
> -               err =3D -ENOENT;
> +               err =3D -EPROTO;

ENOENT as related to "no .BTF section found"... EPROTO would make
sense as well, but I don't think we need to really change anything.
"Protocol error" isn't very meaningful either...


>                 goto done;
>         }
>         btf =3D btf__new(btf_data->d_buf, btf_data->d_size);
> --
> 2.18.4