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 BBCD0C4332F for ; Mon, 7 Nov 2022 11:28:58 +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:MIME-Version:Content-ID:In-Reply-To: References:Message-ID:Date:Subject:CC:To:From:Reply-To:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jBvV5ZhYP1RwzLb1sn/Q8bRlvLTBfCIcauiMppGjRZQ=; b=GAGw8jnSmTv+tz eE/5CR9VCRHAn5wM1+vhYRe+7dPs6quiAECC2HUrbqI6KGBr1oZTZyZuQiLPIHxMPomN/SIcIcAF7 c60Lc1BLDhrrnf/ma8fT9mae19OoWzB2RyI5DRnZqlwUWWAh4yvpSjuLSM6sCIHlSdrn8gpoKEhHZ q493O45DvMSBGcE/TwOdPX62BxuSkp63VxGxPruWecdf8Mk8iUrPw/LJXZvvGnLbuAZvDRcggd+dB gME1bWr37opy/mGcJQyIQfUVVoK7KeO5rs/dg9HS8zLlj/sHZoZM89vx6XPd6rNfu1Tc+4riP1fK/ y0SFVEAy6yzI9ADiZ3HA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1os0IB-00E9D8-EH; Mon, 07 Nov 2022 11:27:51 +0000 Received: from mail-eopbgr60050.outbound.protection.outlook.com ([40.107.6.50] helo=EUR04-DB3-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1os0I8-00E9AE-1X for linux-arm-kernel@lists.infradead.org; Mon, 07 Nov 2022 11:27:49 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Kmx73ek/n/X4gNLuAOCJE8N2KCXA1t3jPYfPYGbhYd0iLu66X30MeKbs7xFfD3iAsgUINVAeog22SqUFUCik/9zVTYDnrXtJuEYoU1WR5a42IA7yKTfKK8KDQJnMkhrM5ggG5vzy4xAqgEnasJPhOZxup7QAFU+f4UQfIJvojp2T2Ah/I359STAmddv1mt0Em5sk2UAEGhnn+ftzxoJjebYA/yLWpt3KD1wd9JFgZ5YZV434TSldG8bEKFP343NpRRfo2jfcfFTblgPu+YxP1rjGCtgh8/bDrmAff8WaS6PO6YITWxBoceJbtUGEltqbzk/4AUSFyIAS3CCHIRwF4g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=KvT3ukkDNAaUwpTtzUVC8HlFP+3P78SgZPtxxeWqn+o=; b=j8g+Qm47IwGd61rYBTrCKixtY3pygpYHYDQn4lzwCsyMqG8eALMRy488Li1p5x+e9zx2QUAJF7SF96vF6IgOcgwvgCSc4mmkTWRFUJHyY5KWrNITOo25U8C7ftHYknEZo5+vOYzj5Yk9Wg2EsWjveY4/LEphuytMBhz3HyLWmC4s0XuESkUMJb0uHhx0NJdgAN9L8Aqcx5z3NfZSOKSJXywx/7Ua+ni7FV1SSs7L1R4W4KnEbnDBb+6UbTRy+n3lCU7z7PJwQtIoRdGud9a5n+pUYAmYeQicXrh+Aw/aaKjHU9m8mhFfxn9+6yW9rnEX/XZdZiL/o7ngAkSmFGG5FQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=KvT3ukkDNAaUwpTtzUVC8HlFP+3P78SgZPtxxeWqn+o=; b=Hc22qd2LPpHs99AzZDkVNuSpHSS/pM6NJ5izzsIJrW3QCiOwg4BCAvx8LVBGj2zKyeJRwc/S62aCaY/uCuVmjd+XPO4SB9cWbFoPw2TCBQ/6AzjvR4UzEByx0OJCJV31w41Ou6HhJQsCkXY/H/f11LrNp1wzL7t1lQCh/4Dm660= Received: from VI1PR04MB5136.eurprd04.prod.outlook.com (2603:10a6:803:55::19) by PAXPR04MB8270.eurprd04.prod.outlook.com (2603:10a6:102:1c7::24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5791.20; Mon, 7 Nov 2022 11:27:38 +0000 Received: from VI1PR04MB5136.eurprd04.prod.outlook.com ([fe80::4a73:29eb:28e3:f66d]) by VI1PR04MB5136.eurprd04.prod.outlook.com ([fe80::4a73:29eb:28e3:f66d%7]) with mapi id 15.20.5791.024; Mon, 7 Nov 2022 11:27:37 +0000 From: Vladimir Oltean To: Jakub Kicinski CC: Maxime Chevallier , "davem@davemloft.net" , Rob Herring , Krzysztof Kozlowski , Eric Dumazet , Paolo Abeni , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "devicetree@vger.kernel.org" , "thomas.petazzoni@bootlin.com" , Andrew Lunn , Florian Fainelli , Heiner Kallweit , Russell King , "linux-arm-kernel@lists.infradead.org" , Luka Perkov , Robert Marko , Andy Gross , Bjorn Andersson , Konrad Dybcio Subject: Re: [PATCH net-next v8 3/5] net: dsa: add out-of-band tagging protocol Thread-Topic: [PATCH net-next v8 3/5] net: dsa: add out-of-band tagging protocol Thread-Index: AQHY8HTAfetHoGxM5E6HcRPQNrr8s64vpgIAgAOw8wA= Date: Mon, 7 Nov 2022 11:27:37 +0000 Message-ID: <20221107112736.mbdfflh6z37sijwg@skbuf> References: <20221104174151.439008-1-maxime.chevallier@bootlin.com> <20221104174151.439008-4-maxime.chevallier@bootlin.com> <20221104200530.3bbe18c6@kernel.org> In-Reply-To: <20221104200530.3bbe18c6@kernel.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; x-ms-publictraffictype: Email x-ms-traffictypediagnostic: VI1PR04MB5136:EE_|PAXPR04MB8270:EE_ x-ms-office365-filtering-correlation-id: d7d7759f-cf23-4e64-ae03-08dac0b312ba x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:VI1PR04MB5136.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(4636009)(7916004)(376002)(136003)(39860400002)(346002)(396003)(366004)(451199015)(86362001)(38070700005)(7416002)(5660300002)(44832011)(2906002)(6506007)(26005)(9686003)(1076003)(186003)(38100700002)(83380400001)(122000001)(6512007)(66899015)(66946007)(76116006)(54906003)(33716001)(4326008)(66446008)(66556008)(91956017)(64756008)(66476007)(6916009)(8676002)(8936002)(316002)(71200400001)(6486002)(478600001)(41300700001)(10944003);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?Zw8uqw0Y2RI3T5fYA7KYyF4BtS8ypcG/au66pPGGi3qb9dwjlpVC3slTJuIV?= =?us-ascii?Q?oUu4C9LNYetvy/PF8+mkn1mXEs7P1sQ1A+eRkgojLXpG96FQsn+d/NKd/Vvl?= =?us-ascii?Q?ulYilGLSmThzRuIM/gLQgn0vu5spVpbpQVVjppcM8wosJe7tb/K5YaHR6JdY?= =?us-ascii?Q?CEgLYP/bxvaaj7CSl5gsh/3JBZ5O0lgjGGLyDyUyjKe+VCfKtW2jfFpeEywI?= =?us-ascii?Q?FT2te7+HCOpMqB133SIHcQ/jEChuJVezQG9xvsPywxQOlyBIIW51mpkL0NOe?= =?us-ascii?Q?6MsWEyxFWDdpaq7SQgOtBjmtHdElrArlWipRVfyd+FgID19nwuKCRPO9SySq?= =?us-ascii?Q?hcBPSYRqUZ6ye+IwF/eu0qq8POniFKiYPeY/JSPl0JoTiVa3AOslwpLXpJ69?= =?us-ascii?Q?ghkX64E1XbhndyTfYYSmfsvPKJF/wFqGW/NmUvMkn9LpUdJL3/PJfr2SvzXB?= =?us-ascii?Q?EmxasBypqTaFFePzwTjpKGP65kjOp6mReFc0uiYpxRA6uVHlE18d2ivM+WiF?= =?us-ascii?Q?2uUMguvkCNJYk0zsGZuJB6Bb8D/W4c4oBu28y4NBtywUZ5vUbtO3ey8eyXjS?= =?us-ascii?Q?2RXJdWURR8ZG1YFHpkJo9rJmzrCZ3XAHsxg8nB8tYK6nBanPjR4uv5gHBhO1?= =?us-ascii?Q?W8oZmQRT2uM6IH9uIAssC0rn9RAyYdsyeCic10J7AfGuJKcUnkAegTK/6SE+?= =?us-ascii?Q?ailApkgktcHSZt84U+vNy9M/1PkvxGk/5aZY0Wv2nJltJnRu+/1tvus52Dk1?= =?us-ascii?Q?ZaihP9PbqN51z6NsD5z9UJrqBEjfm/Ms4PNzBsno7/U0oYSuyeYo2YMGtV7G?= =?us-ascii?Q?wpuwQ0HU+Gb88N0aZEm046JU+lkXRv7NEomaVKmMzryXqrdKxg9C2FPcnUW5?= =?us-ascii?Q?5ZID2+dJMOAceWL3Gdop8XMbgM374foFiCmA4pG40Fwfbefl3V7cigdzZxRv?= =?us-ascii?Q?Kkyw6O75y+O+ueTIJ36jY/MoPps3CT7ydRnEAli/TATya5MiE+NZhX4rVCYK?= =?us-ascii?Q?Z8g4YUXWbTKu5D7IM8pCzzbgaUletoeVDwNjkoVameUn/LuvoQ+Q7IMAuYFH?= =?us-ascii?Q?qi2fzsIRBtv+m2EyM+UkoIP8tPbsi92BQhkHMKeiRAxLqGoph67C+oFAWQk3?= =?us-ascii?Q?DpvtnYiQKWNBHI0l35bsnbLvNt63PLoH/Oql2jIdLkEUvJaH5tzoXl94uCN1?= =?us-ascii?Q?DqjcbPSQ32UBn/AthaxmMXX97hfSknbd/TEAnGVifxetnkEh2sk7qJotzzVp?= =?us-ascii?Q?bEPSrYSlZA2obL2jp+pRgRschJ1P9kuQUILwqx8lVK4KEGqlE/AY7caaA/LY?= =?us-ascii?Q?bTmgLayCDn3H55aRRvt32yA8kMaZz9K1Qa0GFLYHi2cxETS8PBK2i8q3ZMPD?= =?us-ascii?Q?5SzTn9n/eMcQalehWeMV+WSrpLxlNmKWmUoqT0szGuIs+TgtuFiwXzt0zQHh?= =?us-ascii?Q?9hcNkLIYZ9kSmUubfXHl4govccZ0YKeZgmJ8Gj7UkoVWlMxiayEt+HBbNXOA?= =?us-ascii?Q?EX4TYph6gnccIll2q6vumKhTZ7yD0wX9WXeu/liXkQUrKLK6X517ffG0HhM1?= =?us-ascii?Q?18vYFvMWmEx5aHObrQl+UmLBkBRYb4xsAb44c+MuyRqYrhJ3EjYUS5PNvHua?= =?us-ascii?Q?Fg=3D=3D?= Content-ID: MIME-Version: 1.0 X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5136.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: d7d7759f-cf23-4e64-ae03-08dac0b312ba X-MS-Exchange-CrossTenant-originalarrivaltime: 07 Nov 2022 11:27:37.2093 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: RIMC/2yovuY6iIB187GPsYmZJr+9Tw8cbnJ4q+osUqTJruC23a3DZePbKhSrp+dqCWi9G3dUdnbhY2TiQe5DIg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PAXPR04MB8270 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221107_032748_113486_E02CF1BE X-CRM114-Status: GOOD ( 18.03 ) 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 Hi Jakub, On Fri, Nov 04, 2022 at 08:05:30PM -0700, Jakub Kicinski wrote: > On Fri, 4 Nov 2022 18:41:49 +0100 Maxime Chevallier wrote: > > Add a new tagging protocol based on SKB extensions to convey the > > information about the destination port to the MAC driver > > This is what METADATA_HW_PORT_MUX is for, you shouldn't have > to allocate a piece of memory for every single packet. Since this is the model that skb extensions propose and not something that Maxime invented for this series, I presume that's not such a big deal? What's more, couldn't this specific limitation of skb extensions be addressed in a punctual way, via one-time calls to __skb_ext_alloc() and fast path calls to __skb_ext_set()? I'm unfamiliar to the concept of destination cache entries and even more so to the concept of struct dst_entry * carrying metadata. I suppose the latter were introduced for lack of space in struct sk_buff, to carry metadata between layers that aren't L3/L4 (where normal dst_entry structs are used)? What makes metadata dst's preferable to skb extensions? The latter are more general; AFAIK they can be used between any layer and any other layer, like for example between RX and TX in the forwarding path. Side note, I am not exactly clear what are the lifetime guarantees of a metadata dst entry, and if DSA's use would be 100% safe (DSA is kind of L3, since it has an ETH_P_XDSA packet_type handler, not an rx_handler). More importantly, what happens if a DSA switch is used together with a SRIOV-capable DSA master which already uses METADATA_HW_PORT_MUX for PF-VF communication? (if I understood the commit message of 3fcece12bc1b ("net: store port/representator id in metadata_dst") correctly) _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel