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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EEDA5C0502A for ; Sat, 27 Aug 2022 13:55:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=1mLsUaMhY8cg/XXAyJIeMqeonGrqMpy+6U2DNPUbc8I=; b=fFFfCPFMnLICbE c1nCro+ZV8HCoJKQTLx8GTTRJ1dTjYA4Wq4Ujbb2vlNsTY1sHDMA/Yu+PPaNoaOtf6/A4eFeUOcZU 8mldHU0V+J0grQIIZE32iaRAt/hLuakZB+P+Sxfi/4Y4ovD0cGC/DjpMOrHRLxYouMOo3iIz3Y0pm ZYJmjEg2kbeqImnASuSbRBhI/l1wtZN7Gle3dWLxrQ9akjEwOr1pmKQUX8SKudW4HSUtt17M2jqK3 gHmufJCa5RaL9fiE1K8ZpB+51/c+ZU1HR302Co+b6LUBJGkoDjXSomy322XyXTCzIzo1hvo5KrnUU NuGQsQ+vkuYuDnfrvJUw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oRwGh-00B8iV-P6; Sat, 27 Aug 2022 13:54:35 +0000 Received: from mail-ej1-x632.google.com ([2a00:1450:4864:20::632]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oRwGc-00B8L2-72 for linux-arm-kernel@lists.infradead.org; Sat, 27 Aug 2022 13:54:31 +0000 Received: by mail-ej1-x632.google.com with SMTP id kk26so7743585ejc.11 for ; Sat, 27 Aug 2022 06:54:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=blackwall-org.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc; bh=8CiaLkECx3krBdKp6oIvGxj9L4zpqrT521rHLsVwe9c=; b=g1jkYz6hbaud7MJPfP0jk8kKHIWsdovgRzcgSUPODZpbjnDzLbWqeUUvMfhcoOvP2o htWSK5oUojOo772tVxb2ovafBDv5nHDssuSAXh0GJ8cr7DNbVH/vcT15T6DsrywtkG5L 9N2MXav1SOO5iaoM2/si+QncOtmAC0ORMqsdfWEui/zHqOVusXm259fNbVucOTCO+opN 5uXJo1y/7kZboMlhv5jq7zi5Bl/1QIwfHlz+GnMU49Cg/+iICR3oJzR79/HXC4KyJO1N JcH24SsTQu4KQUwyRQaXQbX4+AADrP7Ie842gQXGkPCgI4H7n1r5lA5bPBLHy+glgCN6 L/Iw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc; bh=8CiaLkECx3krBdKp6oIvGxj9L4zpqrT521rHLsVwe9c=; b=FMm5kNa2AoquCeB1c9iy48GRrAW34bW8sJC0OJtSuLukSIWge3wIVU9wTJqefL6gTO IE/vvXQfje7G45w9Dmz5rJYjmWoTYpyz6Yu1K9D9t90sopqWoyVH/PSvjMV9aTS/uAQV 3t6jkRKQU7hJwMsIETIQrjc7XMoOkK5AvmPRunr+yO0IpU2ZKVgce/xbKebgzdO5aJ1T +P8mJ/VQT3DN2arZ3VcnvTjJ8mT3RDtlXM0pDGUKMcyz45gtzYCvRjw52gx4aDs7fq5y ZrAxtOF+CElWY4TLVf4ZBZ5SQr6TULCeyS+x93sqyqFpHH96HEbiVNFJiNjjAPn+LYVH a0nA== X-Gm-Message-State: ACgBeo0dyzcoPxzNq3xwL3SYy/cR3+tZ9YkOng1rxfGmFxFjGtr5Qak9 H1AK3KrXi/KvyarLppmdSxyQhQ== X-Google-Smtp-Source: AA6agR7Ggm9FNAtOJDfVc+2duDQAqokmt0wFwHO5MhLEgQCeXkyrdXp9PBkVxYqT3pzjDOoS/CBgwA== X-Received: by 2002:a17:906:6a03:b0:730:a20e:cf33 with SMTP id qw3-20020a1709066a0300b00730a20ecf33mr8607603ejc.620.1661608464159; Sat, 27 Aug 2022 06:54:24 -0700 (PDT) Received: from [192.168.0.111] (87-243-81-1.ip.btc-net.bg. [87.243.81.1]) by smtp.gmail.com with ESMTPSA id c17-20020a17090618b100b007311eb42e40sm2107674ejf.54.2022.08.27.06.54.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 27 Aug 2022 06:54:23 -0700 (PDT) Message-ID: Date: Sat, 27 Aug 2022 16:54:21 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Subject: Re: [PATCH v5 net-next 1/6] net: bridge: add locked entry fdb flag to extend locked port feature Content-Language: en-US To: Ido Schimmel Cc: Hans Schultz , davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, Florian Fainelli , Andrew Lunn , Vivien Didelot , Vladimir Oltean , Eric Dumazet , Paolo Abeni , Kurt Kanzenbach , Hauke Mehrtens , Woojung Huh , UNGLinuxDriver@microchip.com, Sean Wang , Landen Chao , DENG Qingfang , Matthias Brugger , Claudiu Manoil , Alexandre Belloni , Jiri Pirko , Ivan Vecera , Roopa Prabhu , Shuah Khan , Christian Marangi , Daniel Borkmann , Yuwei Wang , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, bridge@lists.linux-foundation.org, linux-kselftest@vger.kernel.org References: <20220826114538.705433-1-netdev@kapio-technology.com> <20220826114538.705433-2-netdev@kapio-technology.com> From: Nikolay Aleksandrov In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220827_065430_300000_D1934577 X-CRM114-Status: GOOD ( 35.12 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 27/08/2022 16:17, Ido Schimmel wrote: > On Sat, Aug 27, 2022 at 02:30:25PM +0300, Nikolay Aleksandrov wrote: >> On 26/08/2022 14:45, Hans Schultz wrote: >> Please add the blackhole flag in a separate patch. > > +1 > > [...] > >>> @@ -185,6 +196,9 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb >>> if (test_bit(BR_FDB_LOCAL, &dst->flags)) >>> return br_pass_frame_up(skb); >>> >>> + if (test_bit(BR_FDB_BLACKHOLE, &dst->flags)) >>> + goto drop; >>> + >> Not happy about adding a new test in arguably the most used fast-path, but I don't see >> a better way to do blackhole right now. Could you please make it an unlikely() ? >> >> I guess the blackhole flag will be allowed for user-space to set at some point, why >> not do it from the start? >> >> Actually adding a BR_FDB_LOCAL and BR_FDB_BLACKHOLE would be a conflict above - >> the packet will be received. So you should move the blackhole check above the >> BR_FDB_LOCAL one if user-space is allowed to set it to any entry. > > Agree about unlikely() and making it writeable from user space from the > start. This flag is different from the "locked" flag that should only be > ever set by the kernel. > > Regarding BR_FDB_LOCAL, I think BR_FDB_BLACKHOLE should only be allowed > with BR_FDB_LOCAL as these entries are similar in the following ways: > > 1. It doesn't make sense to associate a blackhole entry with a specific > port. The packet will never be forwarded to this port, but dropped by > the bridge. This means user space will add them on the bridge itself: > Right, good point. > # bridge fdb add 00:11:22:33:44:55 dev br0 self local blackhole > > 2. If you agree that these entries should not be associated with a > specific port, then it also does not make sense to subject them to > ageing and roaming, just like existing local/permanent entries. > > The above allows us to push the new check under the BR_FDB_LOCAL check: > hmm.. so only the driver will be allowed to add non-BR_FDB_LOCAL blackhole entries with locked flag set as well, that sounds ok as they will be extern_learn and enforced by it. It is a little discrepancy as we cannot add similar entries in SW but it really doesn't make any sense to have blackhole fdbs pointing to a port. SW won't be able to have a locked entry w/ blackhole set, but I like that it is hidden in the fdb local case when fwding and that's good enough for me. > diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c > index 68b3e850bcb9..4357445529a5 100644 > --- a/net/bridge/br_input.c > +++ b/net/bridge/br_input.c > @@ -182,8 +182,11 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb > if (dst) { > unsigned long now = jiffies; > > - if (test_bit(BR_FDB_LOCAL, &dst->flags)) > + if (test_bit(BR_FDB_LOCAL, &dst->flags)) { > + if (unlikely(test_bit(BR_FDB_BLACKHOLE, &dst->flags))) > + goto drop; > return br_pass_frame_up(skb); > + } > > if (now != dst->used) > dst->used = now; _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel