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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 3039EC3A5A3 for ; Sun, 25 Aug 2019 18:32:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 07CC12173E for ; Sun, 25 Aug 2019 18:32:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="veXy1zOZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728898AbfHYScV (ORCPT ); Sun, 25 Aug 2019 14:32:21 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:36577 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728818AbfHYScV (ORCPT ); Sun, 25 Aug 2019 14:32:21 -0400 Received: by mail-wm1-f66.google.com with SMTP id g67so13724971wme.1 for ; Sun, 25 Aug 2019 11:32:19 -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; bh=oZOnUnIyGaNuUoHr2Bi1L/ITN5tvgAtjXraJPK/g5dY=; b=veXy1zOZrQL92GfO9WkpuhY19AYhxBrVYiHDCvAGXRlVffJd0VpeshjcaCTfKmoJ/r RsliCYQhhVK82eyy6NFJqVacU5/H0OSv/nLWrKmGyc4PCDGD+Fd6PmIlwtOScyWmtvxY e37qLXLHqS/0+vUMVZNShjF/p1pIUUoN2ckZ901BuoRHFLZAB7BsFYa6stfjGJn3boMY GDoYpJOJ/gfvVMWniAXtYrYt5AUjCKUZF/weoMz66AL9W/0IJYwNp42rTqaE3tWTSSvl ZqtQiZUo7ItTW9LpDcxwi1NdoqrdPyJUBQT8y4JaBhyegekBuT8t8V1KXTp5eeaDlLuv 2q/w== 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; bh=oZOnUnIyGaNuUoHr2Bi1L/ITN5tvgAtjXraJPK/g5dY=; b=p4BAfVD4JGKCZxzb5OCas9UU3jjmlVAs96fbm/xQX51mL4TGUlHhvvN3kU+r0htVzX Y78k11EwEfFl0hUEXlo6/Xdwpf8qpWrU1HxJ0gmpUXht7w8kcvqyKIR+sZ3OTo7qwz6E VIEOdgXTJrvJqOUu5KTwWiqboSLc4r/aj0QBVg3CSG/+6wd9JSPctXO9Ew7LIHcGPCnL wTPS0sWCUwniFbAWfFzZQfO/T/IiMXHGEoSD8IF3zDdp8MzZP9SFDvPh4s3YaMsAVSdW laARL6On2Id7JIrZlgR1XmFCI8dbEOCDnaIn+IiaTQxGAjtqzp0cWvmBwen8YQPDlEVg tsCA== X-Gm-Message-State: APjAAAUQOjDXerhIdW7Po4R8v5gJx92QOzwcRaR07GO+x37wo+ky9AFE dLP5NLg5+TNzj+K9lxXv/2Y= X-Google-Smtp-Source: APXvYqz0lF9sro1mEO136pLGWXM1ZeLEzKLoiobQlDhz+qLRlVKgl6q4o50FtnvcV7VD4qiAL/HS/Q== X-Received: by 2002:a1c:a481:: with SMTP id n123mr16155015wme.123.1566757938904; Sun, 25 Aug 2019 11:32:18 -0700 (PDT) Received: from localhost.localdomain ([86.126.25.232]) by smtp.gmail.com with ESMTPSA id t19sm8952842wmi.29.2019.08.25.11.32.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 25 Aug 2019 11:32:18 -0700 (PDT) From: Vladimir Oltean To: f.fainelli@gmail.com, vivien.didelot@gmail.com, andrew@lunn.ch, davem@davemloft.net Cc: netdev@vger.kernel.org, Vladimir Oltean Subject: [PATCH net] net: dsa: tag_8021q: Future-proof the reserved fields in the custom VID Date: Sun, 25 Aug 2019 21:32:12 +0300 Message-Id: <20190825183212.11426-1-olteanv@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org After witnessing the discussion in https://lkml.org/lkml/2019/8/14/151 w.r.t. ioctl extensibility, it became clear that such an issue might prevent that the 3 RSV bits inside the DSA 802.1Q tag might also suffer the same fate and be useless for further extension. So clearly specify that the reserved bits should currently be transmitted as zero and ignored on receive. The DSA tagger already does this (and has always did), and is the only known user so far (no Wireshark dissection plugin, etc). So there should be no incompatibility to speak of. Fixes: 0471dd429cea ("net: dsa: tag_8021q: Create a stable binary format") Signed-off-by: Vladimir Oltean --- net/dsa/tag_8021q.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c index 6ebbd799c4eb..67a1bc635a7b 100644 --- a/net/dsa/tag_8021q.c +++ b/net/dsa/tag_8021q.c @@ -28,6 +28,7 @@ * * RSV - VID[9]: * To be used for further expansion of SWITCH_ID or for other purposes. + * Must be transmitted as zero and ignored on receive. * * SWITCH_ID - VID[8:6]: * Index of switch within DSA tree. Must be between 0 and @@ -35,6 +36,7 @@ * * RSV - VID[5:4]: * To be used for further expansion of PORT or for other purposes. + * Must be transmitted as zero and ignored on receive. * * PORT - VID[3:0]: * Index of switch port. Must be between 0 and DSA_MAX_PORTS - 1. -- 2.17.1