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From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Wed, 21 Sep 2022 17:29:52 -0700
Message-ID: <CAEf4BzYTXPhiXYDoqDgU5o4rPWZ-OXo0f4xtuJdi22tHYyWrqA@mail.gmail.com>
Subject: Re: [PATCH v2] libbpf: Support raw btf placed in the default path
To:     Yonghong Song <yhs@fb.com>
Cc:     Tao Chen <chentao.kernel@linux.alibaba.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>, netdev@vger.kernel.org,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
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On Mon, Sep 19, 2022 at 8:40 PM Yonghong Song <yhs@fb.com> wrote:
>
>
>
> On 9/12/22 9:43 AM, Tao Chen wrote:
> > Now only elf btf can be placed in the default path(/boot), raw
> > btf should also can be there.
>
> There are more default paths than just /boot. Also some grammer
> issues in the above like 'should also can be'.
>
> Maybe the commit message can be changed like below.
>
> Currently, the default vmlinux files at '/boot/vmlinux-*',
> '/lib/modules/*/vmlinux-*' etc. are parsed with 'btf__parse_elf'
> to extract BTF. It is possible that these files are actually
> raw BTF files similar to /sys/kernel/btf/vmlinux. So parse
> these files with 'btf__parse' which tries both raw format and
> ELF format.
>

Thanks, Yonghong, I used this description verbatim when applying. Also
added a sentence on why users might use this instead of providing the
btf_custom_path option.

> It would be great if you can add more information on why
> '/boot/vmlinux-*' or '/lib/modules/*/vmlinux-*' might be
> a raw BTF file in your system.
>
> >
> > Signed-off-by: Tao Chen <chentao.kernel@linux.alibaba.com>
>
> Ack with some commit message changes in the above.
>
> Acked-by: Yonghong Song <yhs@fb.com>