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Date:   Mon, 19 Sep 2022 20:40:27 -0700
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Subject: Re: [PATCH v2] libbpf: Support raw btf placed in the default path
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To:     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>
Cc:     netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <3f59fb5a345d2e4f10e16fe9e35fbc4c03ecaa3e.1662999860.git.chentao.kernel@linux.alibaba.com>
From:   Yonghong Song <yhs@fb.com>
In-Reply-To: <3f59fb5a345d2e4f10e16fe9e35fbc4c03ecaa3e.1662999860.git.chentao.kernel@linux.alibaba.com>
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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.

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>