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Mon, 21 Oct 2024 16:41:38 -0700 Date: Mon, 21 Oct 2024 16:41:37 -0700 From: Nicolin Chen To: Alexey Kardashevskiy CC: , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v3 04/11] iommufd/viommu: Add IOMMU_VIOMMU_ALLOC ioctl Message-ID: References: <352e1701acdec6e038ccddf02227be3a1670706e.1728491453.git.nicolinc@nvidia.com> <6ac9e666-75c3-4cc3-beed-03295368294c@amd.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <6ac9e666-75c3-4cc3-beed-03295368294c@amd.com> X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS3PEPF000099DD:EE_|PH8PR12MB7325:EE_ X-MS-Office365-Filtering-Correlation-Id: 820cd75e-dc62-427a-a3ae-08dcf229f02b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|82310400026|36860700013|1800799024; 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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Oct 2024 23:41:51.5334 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 820cd75e-dc62-427a-a3ae-08dcf229f02b X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: DS3PEPF000099DD.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB7325 On Mon, Oct 21, 2024 at 07:11:47PM +1100, Alexey Kardashevskiy wrote: > > + /* > > + * A real physical IOMMU instance would unlikely get unplugged, so the > > + * life cycle of this iommu_dev is guaranteed to stay alive, mostly. A > > + * pluggable IOMMU instance (if exists) is responsible for refcounting > > + * on its own. > > "Assume IOMMUs are unpluggable (the most likely case)" would do imho, > all these "unlikely" and "mostly" and "if exists" confuse. Done. ----------------------------------------------------------------- @@ -63,13 +63,7 @@ int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd) viommu->type = cmd->type; viommu->ictx = ucmd->ictx; viommu->hwpt = hwpt_paging; - - /* - * A real physical IOMMU instance would unlikely get unplugged, so the - * life cycle of this iommu_dev is guaranteed to stay alive, mostly. A - * pluggable IOMMU instance (if exists) is responsible for refcounting - * on its own. - */ + /* Assume physical IOMMUs are unpluggable (the most likely case) */ viommu->iommu_dev = __iommu_get_iommu_dev(idev->dev); refcount_inc(&viommu->hwpt->common.obj.users); ----------------------------------------------------------------- Thanks Nicolin