netdev - Re: [PATCH 3/5] bpf, docs: Better document the legacy packet access instruction

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Date:   Thu, 3 Feb 2022 09:32:38 -0800
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Christoph Hellwig <hch@....de>
Cc:     Jonathan Corbet <corbet@....net>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Andrii Nakryiko <andrii@...nel.org>,
        Martin KaFai Lau <kafai@...com>,
        Song Liu <songliubraving@...com>, Yonghong Song <yhs@...com>,
        John Fastabend <john.fastabend@...il.com>,
        KP Singh <kpsingh@...nel.org>,
        "open list:DOCUMENTATION" <linux-doc@...r.kernel.org>,
        Network Development <netdev@...r.kernel.org>,
        bpf <bpf@...r.kernel.org>
Subject: Re: [PATCH 3/5] bpf, docs: Better document the legacy packet access instruction

On Mon, Jan 31, 2022 at 10:36 AM Christoph Hellwig <hch@....de> wrote:
> +These instructions are used to access packet data and can only be used when
> +the interpreter context is a pointer to networking packet.  ``BPF_ABS``
...
> +These instructions have an implicit program exit condition as well. When an
> +eBPF program is trying to access the data beyond the packet boundary, the
> +interpreter will abort the execution of the program.

These two places make it sound like it's interpreter only behavior.
I've reworded it like:
-the interpreter context is a pointer to networking packet.  ``BPF_ABS``
+the program context is a pointer to networking packet.  ``BPF_ABS``

-interpreter will abort the execution of the program.
+program execution will be aborted.

and pushed to bpf-next with the rest of patches.