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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 A2C64C433E1 for ; Mon, 17 Aug 2020 19:45:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8456A20658 for ; Mon, 17 Aug 2020 19:45:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597693551; bh=hA1h9wZ8IJcr0MIhQYceFwDgSJwUNP7M6s/QAIjJbUk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=c+9UhEDFJ31Hi2xMD1ltOPkyhxkGJ40aVWYAIlJVSqKYS0SZTNDgG2M/EN6UAXiai x0HGFWOHoknQA1zyf7jSouLck8Q5IK0s4KvSqeGuuidFlWkI99ODC1HI+ns/zDYU0p IAz7yKOxoa41m2BS+5irBTVSiMOdxTQBAksGJCz8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404388AbgHQTpr (ORCPT ); Mon, 17 Aug 2020 15:45:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:44622 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729392AbgHQPVu (ORCPT ); Mon, 17 Aug 2020 11:21:50 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B4B7820716; Mon, 17 Aug 2020 15:21:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597677708; bh=hA1h9wZ8IJcr0MIhQYceFwDgSJwUNP7M6s/QAIjJbUk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yPCxnQ//gy4y67TqFr+t1yWdHDbCKgFCt3mk/TNVoaMxykmU0zej4+XVCZNVbQYWT /P0FXtfI10Ucg/mOtEW+P+ZCgBlCkH447isQgX6lwgSwE1glyDH6ENjaeqKM5IlCPb L0f9s2GpAY4adi8IECccXnisDmV3Lg8bCrN+ZtTc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vladimir Oltean , "David S. Miller" , Sasha Levin Subject: [PATCH 5.8 079/464] net: mscc: ocelot: fix encoding destination ports into multicast IPv4 address Date: Mon, 17 Aug 2020 17:10:32 +0200 Message-Id: <20200817143837.564359473@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143833.737102804@linuxfoundation.org> References: <20200817143833.737102804@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vladimir Oltean [ Upstream commit 0897ecf7532577bda3dbcb043ce046a96948889d ] The ocelot hardware designers have made some hacks to support multicast IPv4 and IPv6 addresses. Normally, the MAC table matches on MAC addresses and the destination ports are selected through the DEST_IDX field of the respective MAC table entry. The DEST_IDX points to a Port Group ID (PGID) which contains the bit mask of ports that frames should be forwarded to. But there aren't a lot of PGIDs (only 80 or so) and there are clearly many more IP multicast addresses than that, so it doesn't scale to use this PGID mechanism, so something else was done. Since the first portion of the MAC address is known, the hack they did was to use a single PGID for _flooding_ unknown IPv4 multicast (PGID_MCIPV4 == 62), but for known IP multicast, embed the destination ports into the first 3 bytes of the MAC address recorded in the MAC table. The VSC7514 datasheet explains it like this: 3.9.1.5 IPv4 Multicast Entries MAC table entries with the ENTRY_TYPE = 2 settings are interpreted as IPv4 multicast entries. IPv4 multicasts entries match IPv4 frames, which are classified to the specified VID, and which have DMAC = 0x01005Exxxxxx, where xxxxxx is the lower 24 bits of the MAC address in the entry. Instead of a lookup in the destination mask table (PGID), the destination set is programmed as part of the entry MAC address. This is shown in the following table. Table 78: IPv4 Multicast Destination Mask Destination Ports Record Bit Field --------------------------------------------- Ports 10-0 MAC[34-24] Example: All IPv4 multicast frames in VLAN 12 with MAC 01005E112233 are to be forwarded to ports 3, 8, and 9. This is done by inserting the following entry in the MAC table entry: VALID = 1 VID = 12 MAC = 0x000308112233 ENTRY_TYPE = 2 DEST_IDX = 0 But this procedure is not at all what's going on in the driver. In fact, the code that embeds the ports into the MAC address looks like it hasn't actually been tested. This patch applies the procedure described in the datasheet. Since there are many other fixes to be made around multicast forwarding until it works properly, there is no real reason for this patch to be backported to stable trees, or considered a real fix of something that should have worked. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/mscc/ocelot.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index f17da67a4622e..d0b79cca51840 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -1605,14 +1605,14 @@ static int ocelot_port_obj_add_mdb(struct net_device *dev, addr[0] = 0; if (!new) { - addr[2] = mc->ports << 0; - addr[1] = mc->ports << 8; + addr[1] = mc->ports >> 8; + addr[2] = mc->ports & 0xff; ocelot_mact_forget(ocelot, addr, vid); } mc->ports |= BIT(port); - addr[2] = mc->ports << 0; - addr[1] = mc->ports << 8; + addr[1] = mc->ports >> 8; + addr[2] = mc->ports & 0xff; return ocelot_mact_learn(ocelot, 0, addr, vid, ENTRYTYPE_MACv4); } @@ -1636,9 +1636,9 @@ static int ocelot_port_obj_del_mdb(struct net_device *dev, return -ENOENT; memcpy(addr, mc->addr, ETH_ALEN); - addr[2] = mc->ports << 0; - addr[1] = mc->ports << 8; addr[0] = 0; + addr[1] = mc->ports >> 8; + addr[2] = mc->ports & 0xff; ocelot_mact_forget(ocelot, addr, vid); mc->ports &= ~BIT(port); @@ -1648,8 +1648,8 @@ static int ocelot_port_obj_del_mdb(struct net_device *dev, return 0; } - addr[2] = mc->ports << 0; - addr[1] = mc->ports << 8; + addr[1] = mc->ports >> 8; + addr[2] = mc->ports & 0xff; return ocelot_mact_learn(ocelot, 0, addr, vid, ENTRYTYPE_MACv4); } -- 2.25.1