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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Niklas =?iso-8859-1?Q?S=F6derlund?= , Biju Das , Claudiu Beznea , Lad Prabhakar , Mitsuhiro Kimura , netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [net-next PATCH 2/2] net: ravb: Fix R-Car RX frame size limit Message-ID: References: <20240615103038.973-1-paul.barker.ct@bp.renesas.com> <20240615103038.973-3-paul.barker.ct@bp.renesas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240615103038.973-3-paul.barker.ct@bp.renesas.com> On Sat, Jun 15, 2024 at 11:30:38AM +0100, Paul Barker wrote: > The RX frame size limit should not be based on the current MTU setting. > Instead it should be based on the hardware capabilities. This is a bit odd. MTU is Maximum Transmission Unit, so clearly is about Tx. MRU does not really exist. Does TCP allow for asymmetric MTU/MRU? Does MTU discovery work correctly for this? In general, it seems like drivers implement min(MTU, MRU) and nothing more. Do you have a real use case for this asymmetry? Andrew