From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH] net: dsa: ksz: Fix port membership Date: Fri, 7 Dec 2018 21:05:25 +0100 Message-ID: <20181207200525.GE1294@lunn.ch> References: <20181207174424.10989-1-marex@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: marex@denx.de, f.fainelli@gmail.com, vivien.didelot@savoirfairelinux.com, Woojung.Huh@microchip.com, UNGLinuxDriver@microchip.com, davem@davemloft.net, netdev@vger.kernel.org To: Tristram.Ha@microchip.com Return-path: Received: from vps0.lunn.ch ([185.16.172.187]:38355 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726047AbeLGUFb (ORCPT ); Fri, 7 Dec 2018 15:05:31 -0500 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: > I think if you do this without setting offload_fwd_mark you will > receive duplicate frame. I don't think it will, at least not in the normal case. The hardware should know the egress port, so there is no need to forward a copy to the CPU. The only time it should forward to the CPU is when the egress port is not known, so it floods. Without offload_fwd_mark set, the SW bridge will flood it back out the ports causing duplication. But that is not too bad. The Marvell driver did this for a while and nothing bad was reported. Andrew