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Date:   Fri, 29 Sep 2023 10:43:03 -0700
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Subject: Re: [PATCH net-next v3] net: ixp4xx_eth: Support changing the MTU
Content-Language: en-US
To:     Linus Walleij <linus.walleij@linaro.org>,
        Krzysztof Halasa <khalasa@piap.pl>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
CC:     <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20230928-ixp4xx-eth-mtu-v3-1-cb18eaa0edb9@linaro.org>
From:   Jacob Keller <jacob.e.keller@intel.com>
In-Reply-To: <20230928-ixp4xx-eth-mtu-v3-1-cb18eaa0edb9@linaro.org>
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On 9/27/2023 3:12 PM, Linus Walleij wrote:
> As we don't specify the MTU in the driver, the framework
> will fall back to 1500 bytes and this doesn't work very
> well when we try to attach a DSA switch:
> 
>   eth1: mtu greater than device maximum
>   ixp4xx_eth c800a000.ethernet eth1: error -22 setting
>   MTU to 1504 to include DSA overhead
> 
> After locating an out-of-tree patch in OpenWrt I found
> suitable code to set the MTU on the interface and ported
> it and updated it. Now the MTU gets set properly.
> 
> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> Changes in v3:
> - Fix some coding style and initialization style.
> - Collect Jacob's review tag.
> - Link to v2: https://lore.kernel.org/r/20230925-ixp4xx-eth-mtu-v2-1-393caab75cb0@linaro.org
> 

Thanks for the cleanups! Looks good to me still.

-Jake