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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 CFB5AC10F13 for ; Sun, 14 Apr 2019 22:31:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 95EB22084D for ; Sun, 14 Apr 2019 22:31:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fU8Vv70Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726480AbfDNWbB (ORCPT ); Sun, 14 Apr 2019 18:31:01 -0400 Received: from mail-lf1-f65.google.com ([209.85.167.65]:44150 "EHLO mail-lf1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725772AbfDNWbA (ORCPT ); Sun, 14 Apr 2019 18:31:00 -0400 Received: by mail-lf1-f65.google.com with SMTP id h18so11492435lfj.11; Sun, 14 Apr 2019 15:30:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qqqZr2kdHJ+mNgq3vg3qQYC4iJwX7twSOJ7XEBxmdIo=; b=fU8Vv70QG/njPSw7KSl5+nvayVjLOghsL995rQR4KYaU+BKZtp5i1PofxeSUJEHvr+ RIQSM23AK4TVvFDW12MFJ262ULEp+UmZCbzuFpverdicgUbqaNWRrIuQZYE00KeO6rdK jLvaJfIFzEW1wnpga0OTfZIQdNCJ0m90c2Oh+gCc1+aZHBN60A5wi7vNbgJEXAs9xn7F ccWeM+6Xdmcr6nxt5FBCQLx9eGr72KfZzdRDxavHe/KFoUpKRwKJE85sOUNJH2ghll1g OEEqVy8YhCTA8wjB212nGJZhOXrKL1eI/E+rpwHQVEShck5jsKZBUt6v6TTevGBcE8rt 8ZVw== 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=qqqZr2kdHJ+mNgq3vg3qQYC4iJwX7twSOJ7XEBxmdIo=; b=aWYVI06raR28TVZ4gqAJECO09ghAbRFJUscSIV+xc2mThz5fB9tY3iWk35gdXFe57f Rc/0pQeUaKUPB8IzdMGr6SdUy/YrulGQU0EmdJXvoCgAySLiI/BBTNUuJ1ws3fSSZ45u kX8iP1g548bCpmpAX8bu8C7r1nju3YZFYCTcdm3/J3qHI0k9XQlXqVbAn9MScydVh5uJ F2uy6RD850uw5dPZGTTZ4rNQnzu2CQJ7LuF3EGZeh0V5pG4ebzoRgE407NOgnB1GPtVf mIekj1XpgtbBJUosizAlHuWBnrPEPkoxzDNckWOII2SKyOkF5nfEi6xNOJxC32AsMkWT 9oVg== X-Gm-Message-State: APjAAAWrUefZPMwEz/26/VoFiypTt347EHhcDu18VKH4W+TQFRvfRWq1 d8XWyhLrRF6kfJOawSu/ZNvPHhuFfFjHnZl53Zw= X-Google-Smtp-Source: APXvYqyzEbnutt6nluaztZVu7NiE5LhdbSaKbEXvF5/Ex9nO4JSsMQjCd1vePaGw4Xn/ZazNDCWjwIoBllV0dP0y3tc= X-Received: by 2002:a19:f512:: with SMTP id j18mr31443063lfb.48.1555281058546; Sun, 14 Apr 2019 15:30:58 -0700 (PDT) MIME-Version: 1.0 References: <20190413012822.30931-1-olteanv@gmail.com> <20190413012822.30931-19-olteanv@gmail.com> <20190413163754.GG17901@lunn.ch> <20190414161757.GB10323@lunn.ch> <20190414191318.GE10323@lunn.ch> In-Reply-To: <20190414191318.GE10323@lunn.ch> From: Vladimir Oltean Date: Mon, 15 Apr 2019 01:30:46 +0300 Message-ID: Subject: Re: [PATCH v3 net-next 18/24] net: dsa: sja1105: Add support for traffic through standalone ports To: Andrew Lunn Cc: Florian Fainelli , vivien.didelot@gmail.com, davem@davemloft.net, netdev , linux-kernel@vger.kernel.org, Georg Waibel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 14 Apr 2019 at 22:13, Andrew Lunn wrote: > > On Sun, Apr 14, 2019 at 09:53:42PM +0300, Vladimir Oltean wrote: > > On Sun, 14 Apr 2019 at 19:18, Andrew Lunn wrote: > > > > > > > > > > > + return dsa_8021q_xmit(skb, netdev, ETH_P_EDSA, > > > > > > > > + ((pcp << VLAN_PRIO_SHIFT) | tx_vid)); > > > > > > > > > > > > > > Please don't reuse ETH_P_EDSA. Define an ETH_P_SJA1105. > > > > > > > > > > > > > > > I'm receiving contradictory advice on this. Why should I define a new > > > > ethertype, and if I do, what scope should the definition have (local > > > > to the driver and the tagger, local to DSA, UAPI)? > > > > > > ETH_P_EDSA has a well defined meaning. It is a true global EtherType, > > > and means a Marvell EtherType DSA header follows. > > > > > > You are polluting this meaning of ETH_P_EDSA. Would you put ETH_P_IP > > > or ETH_P_8021AD here? > > > > > > Andrew > > > > You are putting an equality sign here between things that are not quite equal. > > The MEDSA EtherType is used for the same purpose as what I'm using it for. > > I don't think it is. tcpdump will match on this EtherType and decode > what follows as an EDSA header, just in the same way it matches a > ETH_P_IP and decodes what comes next as an IP packet. I also have > wireshark patches, which i never submitted, which do the same. > > Please run tcpdump on the master interface with your test system and > see what it does. > > Andrew It fails to decode the frames, obviously. But so does any other EtherType. Florian was hinting (https://lwn.net/ml/netdev/b52f4cdf-edcf-0757-1d6e-d4a831ec7943@gmail.com/) at the recent pull requests submitted to tcpdump and libpcap that make it possible to decode based on the string in /sys/class/net/${master}/dsa/tagging. I admit I haven't actually tested or studied those closely yet (there are more important things to focus on ATM), but since my driver returns "8021q" in sysfs and yours returns "edsa", I would presume tcpdump could use that information. Anyway, since you obviously know more on this topic than I do, please make me understand what are the real problems in spoofing the Ethertype as a Marvell one. Thanks, -Vladimir