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 AFB07C43334 for ; Fri, 24 Jun 2022 05:41:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230036AbiFXFlZ (ORCPT ); Fri, 24 Jun 2022 01:41:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229571AbiFXFlW (ORCPT ); Fri, 24 Jun 2022 01:41:22 -0400 Received: from NAM12-MW2-obe.outbound.protection.outlook.com (mail-mw2nam12on2084.outbound.protection.outlook.com [40.107.244.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 143756802C; Thu, 23 Jun 2022 22:41:22 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=SUXBRtlMA3iRrfl2LhS2zqYPXwbKdGR/84MfskHzqd1NciSr8/5xlsE2AklVM6X45yOrzmyTW5HqjbCQLa7U1JaCcTuzfWsI2zV2Ab7Z0Eu0yR+jmqr7v5nBxlU6LqEvuqoaAQnbKRCSJUUZX0tBVqgFYd80Bu9Xs5ksh7uteTf40OCl48OYb/cG16cnvtjTv9pTGY6BuK6QwPpjRO6+y13CWfkAcsfalpiv5+526mu+yy58/efAFxy9D+znoDIyK0d1sq/noM4cnnjhWNUhKMkqr9U9hB+JbNflFLZECI/8flHg82R/4RMTuqgvKiZ2Q5K/KuB2NAUz2GDElVH0Cg== 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=91QSENODTttSKeaP20dv8mkbbQwplBwNvAhOA6Dz73g=; b=bQZb3nmHtG6T6pxfi58kP6N2jfaHhui2TdnNRQRmM7klDtl5cRFfqwJjeHO9KsTtmX/qwwrsXPo7Sbi5E2jyWqkB+VT3INLD9JMF6qYixXLVI9IxNpYd0B0SEXSFgJiC7rIx8ZlApmuhRYUS7/lMvzPUNXDLCkkna7OVR3uhqKS90NMV3HcCA680uP0eFRVxM0W4Jv13xuV0J8kBE4vxKsSj4RGp2mJx8iRG0SsuS3zW6bgLIgUGyb5sVJ9yrO+OlyDTJstKLCTnkVZUyZHkR6Hy7cMVmNF347TzKQ5nTP9Har75KexMeTozJz5ObrBa7x1g7CMdqVIQGR88bZZ5mg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 12.22.5.236) smtp.rcpttodomain=arm.com smtp.mailfrom=nvidia.com; dmarc=pass (p=reject sp=reject 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=91QSENODTttSKeaP20dv8mkbbQwplBwNvAhOA6Dz73g=; b=eiqVMkAJ+T8GiUMX0iHsvwsWN9kkxzWidvvG10vA26WbHPlc8TxZm0vRiTJzxh6aav5iye7nYs0z/FFUw3b85LIFdCEzTMoMNZ7ELYg3yahlnLbt8x7pFKdjoTvHXbOW0jTMY6tVAC7xXx1FKi59v5qvuo1eYgG70CzDJGKtO95MHYZEMuIS4ykBjTQosa3iH9UYjEZGyWA9oIh9+Em2v6LWgYKJ+IaAL0QMVbGcwpQ8r6B2M+etw/DRvtmQQPH0pMviEgfOmKj09qGwYTq/ysqjExGuuEvk1WpXFruMtdv0XosZvuwduF5eqh/TQqJ5GrAomLCDENZMD+5Rqxqf/A== Received: from DS7PR05CA0096.namprd05.prod.outlook.com (2603:10b6:8:56::28) by MW3PR12MB4396.namprd12.prod.outlook.com (2603:10b6:303:59::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5373.15; Fri, 24 Jun 2022 05:41:19 +0000 Received: from DM6NAM11FT003.eop-nam11.prod.protection.outlook.com (2603:10b6:8:56:cafe::35) by DS7PR05CA0096.outlook.office365.com (2603:10b6:8:56::28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5395.6 via Frontend Transport; Fri, 24 Jun 2022 05:41:19 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 12.22.5.236) smtp.mailfrom=nvidia.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 12.22.5.236 as permitted sender) receiver=protection.outlook.com; client-ip=12.22.5.236; helo=mail.nvidia.com; pr=C Received: from mail.nvidia.com (12.22.5.236) by DM6NAM11FT003.mail.protection.outlook.com (10.13.173.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.5373.15 via Frontend Transport; Fri, 24 Jun 2022 05:41:19 +0000 Received: from rnnvmail202.nvidia.com (10.129.68.7) by DRHQMAIL109.nvidia.com (10.27.9.19) with Microsoft SMTP Server (TLS) id 15.0.1497.32; Fri, 24 Jun 2022 05:41:18 +0000 Received: from rnnvmail201.nvidia.com (10.129.68.8) by rnnvmail202.nvidia.com (10.129.68.7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.26; Thu, 23 Jun 2022 22:41:17 -0700 Received: from Asurada-Nvidia (10.127.8.10) by mail.nvidia.com (10.129.68.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.26 via Frontend Transport; Thu, 23 Jun 2022 22:41:15 -0700 Date: Thu, 23 Jun 2022 22:41:14 -0700 From: Nicolin Chen To: Yong Wu CC: Baolu Lu , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v3 1/5] iommu: Return -EMEDIUMTYPE for incompatible domain and device/group Message-ID: References: <20220623200029.26007-1-nicolinc@nvidia.com> <20220623200029.26007-2-nicolinc@nvidia.com> <270eec00-8aee-2288-4069-d604e6da2925@linux.intel.com> <8a5e9c81ab1487154828af3ca21e62e39bcce18c.camel@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <8a5e9c81ab1487154828af3ca21e62e39bcce18c.camel@mediatek.com> X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 38d323e9-57b5-4f33-3f02-08da55a42a04 X-MS-TrafficTypeDiagnostic: MW3PR12MB4396:EE_ 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:12.22.5.236;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:InfoNoRecords;CAT:NONE;SFS:(13230016)(4636009)(39860400002)(136003)(376002)(346002)(396003)(36840700001)(46966006)(40470700004)(2906002)(5660300002)(8676002)(70586007)(4326008)(47076005)(55016003)(478600001)(336012)(40460700003)(40480700001)(186003)(966005)(70206006)(7416002)(83380400001)(7406005)(426003)(36860700001)(8936002)(82310400005)(41300700001)(86362001)(81166007)(6916009)(82740400003)(54906003)(33716001)(356005)(26005)(316002)(9686003)(36900700001);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Jun 2022 05:41:19.3015 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 38d323e9-57b5-4f33-3f02-08da55a42a04 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[12.22.5.236];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: DM6NAM11FT003.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW3PR12MB4396 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 24, 2022 at 01:38:58PM +0800, Yong Wu wrote: > > > > diff --git a/drivers/iommu/mtk_iommu_v1.c > > > > b/drivers/iommu/mtk_iommu_v1.c > > > > index e1cb51b9866c..5386d889429d 100644 > > > > --- a/drivers/iommu/mtk_iommu_v1.c > > > > +++ b/drivers/iommu/mtk_iommu_v1.c > > > > @@ -304,7 +304,7 @@ static int mtk_iommu_v1_attach_device(struct > > > > iommu_domain *domain, struct device > > > > /* Only allow the domain created internally. */ > > > > mtk_mapping = data->mapping; > > > > if (mtk_mapping->domain != domain) > > > > - return 0; > > > > + return -EMEDIUMTYPE; > > > > > > > > if (!data->m4u_dom) { > > > > data->m4u_dom = dom; > > > > > > This change looks odd. It turns the return value from success to > > > failure. Is it a bug? If so, it should go through a separated fix > > > patch. > > Thanks for the review:) > > > > > Makes sense. > > > > I read the commit log of the original change: > > > https://lore.kernel.org/r/1589530123-30240-1-git-send-email-yong.wu@mediatek.com > > > > It doesn't seem to allow devices to get attached to different > > domains other than the shared mapping->domain, created in the > > in the mtk_iommu_probe_device(). So it looks like returning 0 > > is intentional. Though I am still very confused by this return > > value here, I doubt it has ever been used in a VFIO context. > > It's not used in VFIO context. "return 0" just satisfy the iommu > framework to go ahead. and yes, here we only allow the shared "mapping- > >domain" (All the devices share a domain created internally). > > thus I think we should still keep "return 0" here. Thanks for the reply. I will just drop the change of this file.