From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38409C4338F for ; Sun, 8 Aug 2021 16:12:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 181BD60C3E for ; Sun, 8 Aug 2021 16:12:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231823AbhHHQMz (ORCPT ); Sun, 8 Aug 2021 12:12:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230169AbhHHQMy (ORCPT ); Sun, 8 Aug 2021 12:12:54 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF764C061760; Sun, 8 Aug 2021 09:12:35 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id u5-20020a17090ae005b029017842fe8f82so16750514pjy.0; Sun, 08 Aug 2021 09:12:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-disposition:content-transfer-encoding; bh=f5fFjNuLaESLtt6NpxalDxQH6QXq4SR6rkuDvkhfkdY=; b=kZ1Y8YHhslgLJBNqqU0v9tleoLWjAmdqD+tYyymu2xJB62MfxAqZRHmZkkr1rU7ZVi ePkUaDXmYH74LuIaIn8fAIJmaIxbQjyYnbeknS/kYcgiTZ4oll7oLajDkSiMDmqkrjFU 0GusmTLlMKK4Fo23xLj429nTEvj+hA46gYFamO5RuWZth4jVV4fv79rDRJLKh+TBHMu1 Ovp36p3+7vLSIDse+TnTIpYxoGV+IUguVw/NJcGMjk8/75hBXAUR4BidPZbcQBaIuwOu 2Jl9n6nxsBeALQm8ehek3v+iHbNfDrLPaqIn+pjBFaUjcxQGKqOw5J/U/BYxuN8XAuMC fYzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-disposition :content-transfer-encoding; bh=f5fFjNuLaESLtt6NpxalDxQH6QXq4SR6rkuDvkhfkdY=; b=WR7QTvxdxoQm1Rj0QPUU7QXvodklTucJPGjbK+DM6RWfu+iefHx5V6bc2UUZg+s6bG sgSKbU/7WmXT1sFkTP/I+8COjFKfoZfxejXC9XTVhxOqoVbfpl2d+uFcmfSRItVXfQ0m E66WKKQIqTNfNGx3gOgEJMU64xmrCZnjirodnFJIpxM3F6Q0u0mAXZaTcENO4lPsWdxm epzXUpVAX5Oa87qre9av8IG7PytDkbvK6OgufwUJXmAOrKi1qkC9AGJiu/muCGV8hIqJ WgWA954C9sUrHfWgzL+y0yxws0+VtLRiUgzcRhfPpDhGka/od9FY+HVizl1Ps+E3dNDm 8rKQ== X-Gm-Message-State: AOAM5332Z34xvTyuf/WmUilcfY+Oo6MnxkAq0W8TCpGLfx7j7Wit2ySm qkOnwl8PIPSJUP8d1ZCF3X0= X-Google-Smtp-Source: ABdhPJxpHd7sA+xj/K264Oysk9odcZnnHttjMMytkovw4nHImrjX41umo5G/CyvxRFzEZwTxDoOzLg== X-Received: by 2002:a17:90b:20b:: with SMTP id fy11mr30703033pjb.79.1628439155383; Sun, 08 Aug 2021 09:12:35 -0700 (PDT) Received: from haswell-ubuntu20.lan ([138.197.212.246]) by smtp.gmail.com with ESMTPSA id x7sm16760227pfn.70.2021.08.08.09.12.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Aug 2021 09:12:34 -0700 (PDT) From: DENG Qingfang To: Vladimir Oltean Cc: Hauke Mehrtens , Andrew Lunn , Vivien Didelot , Florian Fainelli , "David S. Miller" , Jakub Kicinski , Russell King , "open list:NETWORKING DRIVERS" , open list , Ansuel Smith , Jonathan McDowell , Michal =?utf-8?B?Vm9rw6HEjQ==?= , Christian Lamparter , Nishka Dasgupta , John Crispin , Stefan Lippers-Hollmann , Hannu Nyman , Imran Khan , Frank Wunderlich , Nick Lowe , =?iso-8859-1?Q?Andr=E9?= Valentin Subject: Re: [RFC net-next 3/3] net: dsa: tag_qca: set offload_fwd_mark Date: Mon, 9 Aug 2021 00:12:24 +0800 Message-Id: <20210808161224.228001-1-dqfext@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210807225721.xk5q6osyqoqjmhmp@skbuf> References: <20210807120726.1063225-1-dqfext@gmail.com> <20210807120726.1063225-4-dqfext@gmail.com> <20210807225721.xk5q6osyqoqjmhmp@skbuf> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 08, 2021 at 01:57:21AM +0300, Vladimir Oltean wrote: > In this day and age, I consider this commit to be a bug fix, since the > software bridge, seeing an skb with offload_fwd_mark = false on an > offloaded port, will think it hasn't been forwarded and do that job > itself. So all broadcast and multicast traffic flooded to the CPU will > end up being transmitted with duplicates on the other bridge ports. > > When the qca8k tagger was added in 2016 in commit cafdc45c949b > ("net-next: dsa: add Qualcomm tag RX/TX handler"), the offload_fwd_mark > framework was already there, but no DSA driver was using it - the first > commit I can find that uses offload_fwd_mark in DSA is f849772915e5 > ("net: dsa: lan9303: lan9303_rcv set skb->offload_fwd_mark") in 2017, > and then quite a few more followed suit. But you could still blame > commit cafdc45c949b. The driver currently only enables flooding to the CPU port (like MT7530 back then), so offload_fwd_mark should NOT be set until bridge flags offload is supported. > > Curious, I also see that the gswip driver is in the same situation: it > implements .port_bridge_join but does not set skb->offload_fwd_mark. > I've copied Hauke Mehrtens to make him aware. I would rather not send > the patch myself because I would do a rather lousy job and set it > unconditionally to 'true', but the hardware can probably do better in > informing the tagger about whether a frame was received only by the host > or not, since it has an 8 byte header on RX. > > For the record, I've checked the other tagging drivers too, to see who > else does not set skb->offload_fwd_mark, and they all correspond to > switch drivers which don't implement .port_bridge_join, which in that > case would be the correct thing to do.