From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E36CD517 for ; Tue, 5 Sep 2023 13:48:43 +0000 (UTC) Received: from mail-ej1-x62b.google.com (mail-ej1-x62b.google.com [IPv6:2a00:1450:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BF29191; Tue, 5 Sep 2023 06:48:42 -0700 (PDT) Received: by mail-ej1-x62b.google.com with SMTP id a640c23a62f3a-99bcfe28909so363106066b.3; Tue, 05 Sep 2023 06:48:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1693921720; x=1694526520; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=ivI8ki1e5TGUUKYpVg+QTE/tjrcLWAvCLa+dhdl5XEI=; b=CY3j1AHeVNCevs0ooms++jx2DMipFFv4A+FTAGA/1qDIvzPxUkMskJEOlW7O4er9VH 4JdhD+Kc4vas6EV4y0gHrAdWB0Jvt1UegrKsapIxtsZGQRZ8T7D1ye4jH2YkLDCSBQ8K 49Yf5kudHvZDNpsDy/wL6kLVVgnhof+FoqVDR9jjty5rs5GFusIXYLsGJDMC9UQwFizK VWnzQz3urUG3xfduWAjfVWUvz3krAMtMsB3j9XyQ4ka5QxcKK1wYzlDpBD1mtLQz931T kS63lZvLJDa7b9TsILbs0euYnMTqfQMtgpqVHagPP1uQ0wj74RWqPoGat7QlRAu+ZfPq jjWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693921720; x=1694526520; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ivI8ki1e5TGUUKYpVg+QTE/tjrcLWAvCLa+dhdl5XEI=; b=SZFP6RHlWkkQpxD1iTQTDYSPYfiMvFsS+MrxWjdh1CqW/BJ4UceBavoq+y+h3QdNjo 7x1mbS+vk2z+tCSfh7ORnNkg01UOES0ZmynCdY2E/eWmC/xEGgmIMmxGuZDCEaS3cfmM Prcrh2u2a4DcdPyxvTqB37XJ6HI8iKenpGS9TMyYZNzQSzkXfkxbXvFjhrs1Fu7r0SNq vIP4S2XXYPAp0SA9B6LkuRIqF6va42NrAszPthilwpwceDqopITjYiAWajGfq0QyHXeW qBaDrzjwOTaz3S5K30s55OkY7KJVoKhVO4IZyqjoYJZOr1vUabNmYWCKi1SULFCmnB8z LxsA== X-Gm-Message-State: AOJu0Yy2xne0jEfS4rCPN/q63RpE2iWGNv4UmJiVUfaql3t1HTWUlW+p HQTFBJkMnssebIeTrYSg50E= X-Google-Smtp-Source: AGHT+IEUa6ooT0fp9TE1xzrdpb7voSWSn4UcmzmYyPMQJD4a+aEz8sShQeZ0Jsw+MpXrM6jeGbKZbQ== X-Received: by 2002:a17:906:116:b0:9a6:4fed:e132 with SMTP id 22-20020a170906011600b009a64fede132mr4279516eje.55.1693921720372; Tue, 05 Sep 2023 06:48:40 -0700 (PDT) Received: from skbuf ([188.26.57.165]) by smtp.gmail.com with ESMTPSA id kg12-20020a17090776ec00b0099364d9f0e6sm7627262ejc.117.2023.09.05.06.48.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 Sep 2023 06:48:40 -0700 (PDT) Date: Tue, 5 Sep 2023 16:48:37 +0300 From: Vladimir Oltean To: Lukasz Majewski Cc: Eric Dumazet , Andrew Lunn , davem@davemloft.net, Paolo Abeni , Woojung Huh , Tristram.Ha@microchip.com, Florian Fainelli , Jakub Kicinski , UNGLinuxDriver@microchip.com, George McCollister , Oleksij Rempel , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 RFC 3/4] net: dsa: hsr: Enable in KSZ9477 switch HW HSR offloading Message-ID: <20230905134837.dzp3yk2hjgt6hf4a@skbuf> References: <20230904120209.741207-1-lukma@denx.de> <20230904120209.741207-1-lukma@denx.de> <20230904120209.741207-4-lukma@denx.de> <20230904120209.741207-4-lukma@denx.de> <20230905103750.u3hbn6xmgthgdpnw@skbuf> <20230905131103.67f41c13@wsk> <20230905130355.7x3vpgdlmdzg6skz@skbuf> Precedence: bulk X-Mailing-List: netdev@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: <20230905130355.7x3vpgdlmdzg6skz@skbuf> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Tue, Sep 05, 2023 at 04:03:55PM +0300, Vladimir Oltean wrote: > > > What are the causes due to which self-address filtering and duplicate > > > elimination only work "most of the time"? > > > > Please refer to section "KSZ9477 CHIP LIMITATIONS" in: > > https://ww1.microchip.com/downloads/en/Appnotes/AN3474-KSZ9477-High-Availability-Seamless-Redundancy-Application-Note-00003474A.pdf > > Ok, so the limitation is a race condition in hardware such that, when > duplicate packets are received on member ports very close in time to > each other, the hardware fails to detect that they're duplicates. It would be good to leave at least the link as part of the comment, if not also a short summary (in case the PDF URL gets moved/removed).