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=-2.7 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 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 13EEDC433E9 for ; Wed, 17 Feb 2021 11:44:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D693564DDA for ; Wed, 17 Feb 2021 11:44:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232062AbhBQLoC (ORCPT ); Wed, 17 Feb 2021 06:44:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231772AbhBQLnf (ORCPT ); Wed, 17 Feb 2021 06:43:35 -0500 Received: from mail-ej1-x62e.google.com (mail-ej1-x62e.google.com [IPv6:2a00:1450:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00D7EC0617A9 for ; Wed, 17 Feb 2021 03:41:20 -0800 (PST) Received: by mail-ej1-x62e.google.com with SMTP id b14so15547827eju.7 for ; Wed, 17 Feb 2021 03:41:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=rA0qOj5Qnr9OamD92a8nM+3wqNABpMmQrWuhOp9m0xA=; b=HKa5r5LLSJrImLuSduT0LUlKvZOkUUEbxeqfv8VUKtmaUrTFEbGRwysvQhE3Q/UqpX 0z2x+D8lzzIhVyR6CLEzFxnbLhVyc4KvJ6nRRo0BwP06gMdsJ808pdHAQIS1picuIHaT EtLtPAnP5XodHT14E+DXB5+u2Kb0Y9Tn3baWxqV6Sz+QlSLoYWo5Q60xce6aueDcFEJK hV4xB0iKQdwtCI+vBPh0ZUnOluk31q7QHxV/tknCEc4iY7x2ko6f1U9fhDPSQRwp/9oh tyFyZvN8kVmCA+h+Jokmxg1PZFh35spRLcetKxOSOAtD/D/6xDebFW9ZTShePOPvGgSO gubw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=rA0qOj5Qnr9OamD92a8nM+3wqNABpMmQrWuhOp9m0xA=; b=pv0PyD2qud5Dvk4xiLHi/GjRdMjXMDN+gi6fpM619pOBAcddplF70JqOC58436bKyX HVjO93u8wkv8/zOUEEwXUYhfh5MglBTsJBIIzJbt8Wgfvb9etwF0KlULtzSTME/BxbNW BZx1hZV3sglkQE5hpMH2F5KS6xHwM9tmMs34DCIA4vsSp7653AzwyKCKBbguVGwgPRUD ct2UjM791Xwn25QTeIBY38usVZQpJHiaC01WMYSn8UlH6nJgL6t9fV3E9H05MR+mTszj I7jQ+XGla6lDk+EcQyfE/AgRXaunExqTh6vTgynXcmWREUl9xhIfte5CM4RuAZWeiaL3 +7rg== X-Gm-Message-State: AOAM5310CM3bVjjMsf2mxVU3rbaRbAcWixi/Z+gVsTbk25QMP1hZ1VWT cmshRW71sQTRKv3lLE/+9mk= X-Google-Smtp-Source: ABdhPJyOVNXYjgTRtz/HOlrB3ZzpDUxOxQlm2HKhrykfL1mSsTVI7Nedunmg2f4z7XkLjOxGBvOSEw== X-Received: by 2002:a17:906:9b4f:: with SMTP id ep15mr24969012ejc.423.1613562078770; Wed, 17 Feb 2021 03:41:18 -0800 (PST) Received: from skbuf (5-12-227-87.residential.rdsnet.ro. [5.12.227.87]) by smtp.gmail.com with ESMTPSA id q14sm936822edw.52.2021.02.17.03.41.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Feb 2021 03:41:18 -0800 (PST) Date: Wed, 17 Feb 2021 13:41:17 +0200 From: Vladimir Oltean To: DENG Qingfang Cc: Andrew Lunn , Linus Walleij , Vivien Didelot , Florian Fainelli , "David S . Miller" , Jakub Kicinski , netdev , Mauri Sandberg Subject: Re: [PATCH] net: dsa: tag_rtl4_a: Support also egress tags Message-ID: <20210217114117.c7oit5tvwjztina2@skbuf> References: <20210216235542.2718128-1-linus.walleij@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Feb 17, 2021 at 01:37:21PM +0800, DENG Qingfang wrote: > On Wed, Feb 17, 2021 at 11:29 AM Andrew Lunn wrote: > > > > > + /* Pad out to at least 60 bytes */ > > > + if (unlikely(eth_skb_pad(skb))) > > > + return NULL; > > > > The core will do the padding for you. Turn on .tail_tag in > > dsa_device_ops. > > > > Please don't. .tail_tag does far more than just padding. Qingfang is right, this is an EtherType tagging protocol not a tail tagger. Note that there was an interesting discussion with Florian and Kuba around the Broadcom switches that require padding for short frames too: https://patchwork.kernel.org/project/netdevbpf/patch/20201101191620.589272-10-vladimir.oltean@nxp.com/