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Date:   Tue, 10 Aug 2021 03:05:27 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Vladimir Oltean <vladimir.oltean@nxp.com>
Cc:     netdev@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        DENG Qingfang <dqfext@gmail.com>,
        John Crispin <john@phrozen.org>,
        Sean Wang <sean.wang@mediatek.com>,
        Landen Chao <Landen.Chao@mediatek.com>
Subject: Re: [RFC PATCH net-next 3/4] net: dsa: create a helper for locating
 EtherType DSA headers on RX
Message-ID: <YRHQ10WEJmKTeOEn@lunn.ch>
References: <20210809115722.351383-1-vladimir.oltean@nxp.com>
 <20210809115722.351383-4-vladimir.oltean@nxp.com>
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On Mon, Aug 09, 2021 at 02:57:21PM +0300, Vladimir Oltean wrote:
> It seems that protocol tagging driver writers are always surprised about
> the formula they use to reach their EtherType header on RX, which
> becomes apparent from the fact that there are comments in multiple
> drivers that mention the same information.
> 
> Create a helper that returns a void pointer to skb->data - 2, as well as
> centralize the explanation why that is the case.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew