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=-14.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 7D268C432BE for ; Wed, 25 Aug 2021 04:59:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65A5F613AD for ; Wed, 25 Aug 2021 04:59:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231935AbhHYFAc (ORCPT ); Wed, 25 Aug 2021 01:00:32 -0400 Received: from mail-co1nam11on2080.outbound.protection.outlook.com ([40.107.220.80]:36993 "EHLO NAM11-CO1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231775AbhHYFA1 (ORCPT ); Wed, 25 Aug 2021 01:00:27 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=WoGDFMtKWH1zft6TWE8S3Q5fOoSC2NKX3k/6Rhd2LgObYR03stzaKWIq+g5UGuUcolRiti63GL+HmzE58TbZP7OMFtUMgTMU9AJikFIwgle1Jn6eh33wrlVOmrAgVHVRtK9MowJIIAjC+h7k9LzcAKR0yBw+OtyOOwyXHdrZNMnb9qy6LFH3wpAtmODBFsoPchaaw/4uuFlcBpK4ViTBD0G3VIjHCmoyLLh5Nv01RYivj1FoB8K6/eVDLTrfx1CVl7Ai8vP1Fu/ompOJKOozMTfW0YwH+9oV7VExVB62OrMclg2R1N5RUXxkg5HMrQlG7wsqSwUK4P2Nd6e7cdh5ZA== 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-SenderADCheck; bh=EwVIaxXKv3fJz+93sMHCMr2vU11fxAj9MPbC2Ej7rKA=; b=lzjQ+Z+GqX4i3/pwTUxR9ECFoVjq36fvAYJ8XoYvXx1dKZ3z1gZpS2TAhldxH2jfmQIBhSL1liySMeQiKSk0HY/aCOQd5T92K+aovkJzNerEB8dw0nvV1U8kQ30JTlmvt/lyg2vQXOo8ZoHPdNTFfJCRHTq7dG1p1PwZkdQpdzxsXp+ZY0GWrnaCc3tOHLk69iRILN947wCpoYpfAVLzNmc/WS+cVcj+dIwWmu1LVB+xzso1oZp8bu7mczEcnpmMZA12aI8QIsWXMr9Mb9ZB0IcS+2S4nfxBZ7KYOUrMIECZALHgeCws7eC/Fu5nkadn2aAG7sbQ7jkguLJhvgdVIg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 216.228.112.35) smtp.rcpttodomain=huawei.com smtp.mailfrom=nvidia.com; dmarc=pass (p=quarantine sp=none pct=100) action=none header.from=nvidia.com; dkim=none (message not signed); arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=EwVIaxXKv3fJz+93sMHCMr2vU11fxAj9MPbC2Ej7rKA=; b=gV/YAMXQbRqNCyvse4MIc3aLb/TWCu0LvwE8NenN4RNtr6NgdU98qA/VHWGhu7oh379yY1rj7qZJtkNpRsK39TUW6VYaI8mYaIsjrXDA3AqKS8bCdc84QRHA/r8Va7dpUS+MbknmhUQAr1YdqXP50Bhu6ouuM1MFQmyBweUcQpiM0nDLSRyzFLu9zhuR5KGtPtPOclbDvxkV9M1VEy83S0hhWojOR7Naz05obL4dhPWlrBcI5JofP+aU0UWUFJ5SEEvZKBp0JZ+0KPOLGmuziWsDt+CtCJ2/M4yZqLgTdwMvGMFJyP44A3HyvI/QN9gYhfEliQnXkied/vzDm6ktog== Received: from BN6PR1101CA0006.namprd11.prod.outlook.com (2603:10b6:405:4a::16) by MN2PR12MB4238.namprd12.prod.outlook.com (2603:10b6:208:199::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4436.19; Wed, 25 Aug 2021 04:59:40 +0000 Received: from BN8NAM11FT020.eop-nam11.prod.protection.outlook.com (2603:10b6:405:4a:cafe::99) by BN6PR1101CA0006.outlook.office365.com (2603:10b6:405:4a::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4457.17 via Frontend Transport; Wed, 25 Aug 2021 04:59:40 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 216.228.112.35) smtp.mailfrom=nvidia.com; huawei.com; dkim=none (message not signed) header.d=none;huawei.com; dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.112.35 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.112.35; helo=mail.nvidia.com; Received: from mail.nvidia.com (216.228.112.35) by BN8NAM11FT020.mail.protection.outlook.com (10.13.176.223) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.4436.19 via Frontend Transport; Wed, 25 Aug 2021 04:59:39 +0000 Received: from DRHQMAIL107.nvidia.com (10.27.9.16) by HQMAIL111.nvidia.com (172.20.187.18) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 25 Aug 2021 04:59:39 +0000 Received: from [172.27.1.233] (172.20.187.6) by DRHQMAIL107.nvidia.com (10.27.9.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 25 Aug 2021 04:59:30 +0000 Subject: Re: [PATCH rdma-next v4 2/3] lib/scatterlist: Fix wrong update of orig_nents To: Jason Gunthorpe CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , References: <20210824142531.3877007-1-maorg@nvidia.com> <20210824142531.3877007-3-maorg@nvidia.com> <20210824191248.GY1721383@nvidia.com> From: Maor Gottlieb Message-ID: <4f4a712a-71d4-ebac-48f2-766bfda61f1e@nvidia.com> Date: Wed, 25 Aug 2021 07:59:27 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20210824191248.GY1721383@nvidia.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [172.20.187.6] X-ClientProxiedBy: HQMAIL107.nvidia.com (172.20.187.13) To DRHQMAIL107.nvidia.com (10.27.9.16) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: f39f0131-c144-4fd0-b0b4-08d96785251d X-MS-TrafficTypeDiagnostic: MN2PR12MB4238: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:4502; 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:216.228.112.35;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:schybrid02.nvidia.com;CAT:NONE;SFS:(4636009)(346002)(396003)(39860400002)(136003)(376002)(46966006)(36840700001)(54906003)(7636003)(2906002)(82740400003)(16526019)(8676002)(53546011)(86362001)(36756003)(356005)(5660300002)(82310400003)(47076005)(316002)(7416002)(186003)(6666004)(16576012)(36906005)(26005)(37006003)(70206006)(6862004)(426003)(8936002)(6636002)(478600001)(83380400001)(4326008)(2616005)(15650500001)(70586007)(36860700001)(336012)(31686004)(4744005)(31696002)(43740500002);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2021 04:59:39.8920 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: f39f0131-c144-4fd0-b0b4-08d96785251d X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.112.35];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BN8NAM11FT020.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4238 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/24/2021 10:12 PM, Jason Gunthorpe wrote: > On Tue, Aug 24, 2021 at 05:25:30PM +0300, Maor Gottlieb wrote: >> @@ -514,11 +531,13 @@ struct scatterlist *sg_alloc_append_table_from_pages(struct sg_table *sgt, >> offset = 0; >> cur_page = j; >> } >> - sgt->nents += added_nents; >> + sgt_append->sgt.nents += added_nents; >> + sgt_append->sgt.orig_nents = sgt_append->sgt.nents; >> + sgt_append->prv = s; > Why is nents being touched here? > > Shouldn't it just be > > sgt_append->sgt.orig_nents += added_nents; > sgt_append->prv = s; > > ? In general yes, but all the sg_alloc_* functions update both orig_nents and nents (to same value). May be drivers that pass nents instead of orig_nents to dma_map_sg* (like umem did before this patch set). So I prefer to set it here as well, also not to break sg_alloc_table_from_pages_segment which use the same path. This kind of change could be done very carefully next cycle for all sg_alloc_*. > > Let me know I can fix it > > Jason