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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F95FC5479D for ; Mon, 9 Jan 2023 12:29:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234476AbjAIM30 (ORCPT ); Mon, 9 Jan 2023 07:29:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57022 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237219AbjAIM3O (ORCPT ); Mon, 9 Jan 2023 07:29:14 -0500 Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 85FAF1BE91; Mon, 9 Jan 2023 04:29:12 -0800 (PST) Received: by mail-ej1-x62a.google.com with SMTP id vm8so19664835ejc.2; Mon, 09 Jan 2023 04:29:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=crINwX8GG7oE7iuw+Z+Wz82V7aegfStJZU7gXgsc5Qc=; b=P/IIjdLg2bouOSQCv2Z03ysTzM8CtExWpKYVGm7RPVyMZ5cRimFFXovhV98OwKeeVh 0vaMYwLL5eqTRXLPGb5jcal0YgpDAOPnzOarn3RsCTNO5G71T+I0vcyt+YoXMOml73wH L16uIdbW/mUIj2anFkl6Ww8a0UyZS0sRDliaK50B0PKFQGXP+H8rO612B5zsbLM5R5vS 6OMJflVKJlUYYDqGVpOl5p/UVVqsqxV96XHkJM1QY8pQSU5XbHXPt9ahGS/1zZ5sSMHm 0ptuSn6+n5+jCFD893QTFZsfZdBiYbY1HCYkDJhx3U600CgdfBJDnCa/untfcTWby19Z ucqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=crINwX8GG7oE7iuw+Z+Wz82V7aegfStJZU7gXgsc5Qc=; b=BUMsMRn4eTsKioOnmFhV8SD8SLw2194aAvToXIQ+DwrfjgMES/FCE2om9e4EUTNxes bAArpv1P7QVvmeQayBAHvQbXBCDJiv7FcfGMuFeCLX5lhCq/abahFelLevOYLA4d+E43 oE+HcN8nUqqM8sIlq2IzPtp6vciHg7VqQDIXBOmujfhO0HjaUE6leHaYBJxRhVi8e03U dzr/V4hXFPcmdbqwxQFMRMOX9heI3fs2pTCFY6UBSnkJSfE3Qj4DQtswVN84iCBJkxm0 wpm32hvliqo3mPSqgKzZidtK3C18aKBmsuT4rERxusAwsXdKRMdKteKSpdnOymGAlil9 Q2uA== X-Gm-Message-State: AFqh2kqiHnPd81N0Exmof8So3pyPS1+L6PtfqvmrU8EMlE1jwILitK7r OF2yzzIyaDLOldgQ63sk+E0= X-Google-Smtp-Source: AMrXdXu+jN1Z5u4gvx/HeqOmEL5odydFz75WSlfwSrwQ+II0GJyIu1O/oM6oeG4mZPvmWt34FYk30g== X-Received: by 2002:a17:906:8447:b0:7c4:fa17:7203 with SMTP id e7-20020a170906844700b007c4fa177203mr48361852ejy.63.1673267350944; Mon, 09 Jan 2023 04:29:10 -0800 (PST) Received: from skbuf ([188.27.185.38]) by smtp.gmail.com with ESMTPSA id 18-20020a170906201200b00846734faa9asm3633540ejo.164.2023.01.09.04.29.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Jan 2023 04:29:10 -0800 (PST) Date: Mon, 9 Jan 2023 14:29:08 +0200 From: Vladimir Oltean To: Ido Schimmel Cc: Tobias Waldekranz , davem@davemloft.net, kuba@kernel.org, Nikolay Aleksandrov , Andrew Lunn , Vivien Didelot , Florian Fainelli , Jiri Pirko , Ivan Vecera , Roopa Prabhu , Russell King , Petr Machata , Ido Schimmel , Matt Johnston , Cooper Lees , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bridge@lists.linux-foundation.org Subject: Re: [PATCH v5 net-next 01/15] net: bridge: mst: Multiple Spanning Tree (MST) mode Message-ID: <20230109122908.dn2xlzlbcvfxgeii@skbuf> References: <20220316150857.2442916-1-tobias@waldekranz.com> <20220316150857.2442916-2-tobias@waldekranz.com> <20230109100236.euq7iaaorqxrun7u@skbuf> <20230109115653.6yjijaj63n2v35lw@skbuf> 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 Mon, Jan 09, 2023 at 02:20:02PM +0200, Ido Schimmel wrote: > On Mon, Jan 09, 2023 at 01:56:53PM +0200, Vladimir Oltean wrote: > > On Mon, Jan 09, 2023 at 01:43:46PM +0200, Ido Schimmel wrote: > > > OK, thanks for confirming. Will send a patch later this week if Tobias > > > won't take care of it by then. First patch will probably be [1] to make > > > sure we dump the correct MST state to user space. It will also make it > > > easier to show the problem and validate the fix. > > > > > > [1] > > > diff --git a/net/bridge/br.c b/net/bridge/br.c > > > index 4f5098d33a46..f02a1ad589de 100644 > > > --- a/net/bridge/br.c > > > +++ b/net/bridge/br.c > > > @@ -286,7 +286,7 @@ int br_boolopt_get(const struct net_bridge *br, enum br_boolopt_id opt) > > > case BR_BOOLOPT_MCAST_VLAN_SNOOPING: > > > return br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED); > > > case BR_BOOLOPT_MST_ENABLE: > > > - return br_opt_get(br, BROPT_MST_ENABLED); > > > + return br_mst_is_enabled(br); > > > > Well, this did report the correct MST state despite the incorrect static > > branch state, no? The users of br_mst_is_enabled(br) are broken, not > > those of br_opt_get(br, BROPT_MST_ENABLED). > > I should have said "actual"/"effective" instead of "correct". IMO, it's > better to use the same conditional in the both the data and control > paths to eliminate discrepancies. Without the patch, a user will see > that MST is supposedly enabled when it is actually disabled in the data > path. The discussion is about to get philosophical, but I don't know if it's necessary to make a bug more widespread before fixing it.. The br_mst_used is an optimization to avoid calling br_opt_get() when surely MST is not enabled. There should be no discrepancy between using and not using it, if the static branch works correctly (not the case here). I would also expect that consolidation to be part of net-next though. > > Anyway, I see there's a br_mst_is_enabled() and also a br_mst_enabled()?! > > One is used in the fast path and the other in the slow path. They should > > probably be merged, I guess. They both exist probably because somebody > > thought that the "if (!netif_is_bridge_master(dev))" test is redundant > > in the fast path. > > The single user of br_mst_enabled() (DSA) is not affected by the bug > (only the SW data path is), so I suggest making this consolidation in > net-next after the bug is fixed. OK? Yes, net-next, sure.