From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH] doc: add GRO API requirement in prog_guide
Date: Fri, 4 Jan 2019 11:35:45 -0800
Message-ID: <20190104113545.7d31a819@hermes.lan>
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To: Jiayu Hu <jiayu.hu@intel.com>
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On Tue, 18 Dec 2018 12:25:19 +0800
Jiayu Hu <jiayu.hu@intel.com> wrote:

> +.. note::
> +        To use the GRO library, applications must guarantee that
> +        MBUF->l2_len/l3_len/l4_len/outer_l2_len/outer_l3_len and
> +        MBUF->pkt_len/data_len of input packets are set to correct
> +        values.
> +

This statement seems confusing to me since
this is Generic Receive Offload, and receive buffers come from
the poll mode driver.

Aren't you saying that the PMD must set the correct values.
If this is correct, then any PMD not doing so is buggy.
And should be reported and fixed. If it is really buggy PMD's
then the statement in the programmers guide is not the place to handle
this kind of issue.  Better to just shame the buggy drivers in the
release notes for that NIC.