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=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 73424C64E7C for ; Sun, 29 Nov 2020 19:49:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F9F720829 for ; Sun, 29 Nov 2020 19:49:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=newoldbits-com.20150623.gappssmtp.com header.i=@newoldbits-com.20150623.gappssmtp.com header.b="H+T+i92I" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728605AbgK2TtY (ORCPT ); Sun, 29 Nov 2020 14:49:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728293AbgK2TtX (ORCPT ); Sun, 29 Nov 2020 14:49:23 -0500 Received: from mail-io1-xd43.google.com (mail-io1-xd43.google.com [IPv6:2607:f8b0:4864:20::d43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38ECCC0613D3 for ; Sun, 29 Nov 2020 11:48:37 -0800 (PST) Received: by mail-io1-xd43.google.com with SMTP id r9so9683059ioo.7 for ; Sun, 29 Nov 2020 11:48:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=newoldbits-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=FPVmvGLETfFsJB2bxLaRoGgeBKaIWmMhRnqAH6ezMAc=; b=H+T+i92IFdlJiKZBjnc4EM0zlsqe8bUe9HBv0tElLLwVg/TixUCrOCqiZGPHy/f8Qa ur7FJ8LqAtNkxNvmoim6tc3RQrODIIorOEHs7Md9TRWDwgz76dMq32nQ84ShOMpVxwl+ +qbe9zwLzZdhsa66wd+Ec2CmMdFzgFvgD1CRk2ZUEwVvVrqdiJG2KIAw+DdPRmqoGE7N 240BGnIQB3yi2yqgHXjSA2lZ0tIl2MRx4h04IWVMRBSu7DFKKGc/mGp6FtS28012hAzq R0KV14l+CjJeY+YO8bHo4AGtPlK4dxVlMrk4zE8VPO025rOjPZZfgt2Q32swi/4w1mAj O60Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=FPVmvGLETfFsJB2bxLaRoGgeBKaIWmMhRnqAH6ezMAc=; b=OR4aDwOObCYEWfOTkGgxA2EAuJpzbYKpyCbpeCLp82vft3b+AX78U8gwTBVAIYV2wd vmgbbOVEbL2c0X/QLMX/5oHF0iKo38f4W4iFFtMfSIBq2cMR4x/HuqH8fZneG0iYbctt bVoigV0u4C062Hij6uTQ4cYFJNnI+Sd6DTt196tYDrC8sbLyV+3ROFOavMa7R8Wr39np YtaYWKWmD2a4r5uJ549G+6vOPMg3JPyMWG24UCBmwKV3rJSFP2ymXUhHEjDfkNlWLc5u eqCMkqgBzeeiy5IBm03Gvc3X/sxi8KVdIzbo+7CIebgGwFMgH+OlgMHYbtTRFubJydk3 m5pA== X-Gm-Message-State: AOAM533CMwrIxIatfnUBRjDwp7gug52lYiW5vjENhPN2qsXa4m7i5K0M NuLCKbh9iaJYWeI28PL9n9HV+1eC2vXlW7ePra9QUw== X-Google-Smtp-Source: ABdhPJwI0NK/RFeSd2j+i/hflp834uzdZeBqDSHIW4OBRgMwCQW8k+riyNfPCLUY0BIaZdnasBWX60am7kA/gyeblXo= X-Received: by 2002:a5d:9042:: with SMTP id v2mr12402234ioq.98.1606679316572; Sun, 29 Nov 2020 11:48:36 -0800 (PST) MIME-Version: 1.0 References: <20201129102400.157786-1-jean.pihet@newoldbits.com> <20201129165627.GA2234159@lunn.ch> <20201129193822.GP2234159@lunn.ch> In-Reply-To: <20201129193822.GP2234159@lunn.ch> From: Jean Pihet Date: Sun, 29 Nov 2020 20:48:25 +0100 Message-ID: Subject: Re: [PATCH 1/2] net: dsa: ksz: pad frame to 64 bytes for transmission To: Andrew Lunn Cc: netdev@vger.kernel.org, LKML , Ryan Barnett , Conrad Ratschan , Hugo Cornelis , Arnout Vandecappelle Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andrew, On Sun, Nov 29, 2020 at 8:38 PM Andrew Lunn wrote: > > On Sun, Nov 29, 2020 at 08:34:27PM +0100, Jean Pihet wrote: > > Hi Andrew, > > > > On Sun, Nov 29, 2020 at 5:56 PM Andrew Lunn wrote: > > > > > > On Sun, Nov 29, 2020 at 11:23:59AM +0100, Jean Pihet wrote: > > > > Some ethernet controllers (e.g. TI CPSW) pad the frames to a minimum > > > > of 64 bytes before the FCS is appended. This causes an issue with the > > > > KSZ tail tag which could not be the last byte before the FCS. > > > > Solve this by padding the frame to 64 bytes minus the tail tag size, > > > > before the tail tag is added and the frame is passed for transmission. > > > > > > Hi Jean > > > > > > what tree is this based on? Have you seen > > The patches are based on the latest mainline v5.10-rc5. Is this the > > recommended version to submit new patches? > > No, that is old. Please take a read of: > > https://www.kernel.org/doc/html/latest/networking/netdev-FAQ.html Ok got it, thx! Found the commit 88fda8ee and its parent [1] with the following comment, which seems to indicate that my patch is not needed anymore. Can you confirm? /* For tail taggers, we need to pad short frames ourselves, to ensure + * that the tail tag does not fail at its role of being at the end of + * the packet, once the master interface pads the frame. Account for + * that pad length here, and pad later. ... [1] https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=a3b0b6479700a5b0af2c631cb2ec0fb7a0d978f2 Thx, Jean > > Andrew