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Tsirkin" , Miguel Ojeda , Robin Murphy , rust-for-linux@vger.kernel.org, Sagi Grimberg , Stefano Stabellini , Steven Rostedt , virtualization@lists.linux.dev, Will Deacon , xen-devel@lists.xenproject.org Subject: Re: [PATCH v1 00/16] dma-mapping: migrate to physical address-based API Message-ID: <20250810170202.GQ184255@nvidia.com> References: <20250807141929.GN184255@nvidia.com> <20250809133454.GP184255@nvidia.com> <6cbaa3a3-694e-4951-abb3-b88e6c9d6638@gmail.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6cbaa3a3-694e-4951-abb3-b88e6c9d6638@gmail.com> X-ClientProxiedBy: YT4PR01CA0163.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:ac::16) To CH3PR12MB8659.namprd12.prod.outlook.com (2603:10b6:610:17c::13) Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR12MB8659:EE_|PH7PR12MB5596:EE_ X-MS-Office365-Filtering-Correlation-Id: fec849dc-1ee6-4528-8aba-08ddd82fa0dd X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|366016|1800799024; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?s4vtM7QfcEK3pnSfpgdvdzEG1xxhmc0TDHTkbowPQHBiG7Js+F0EgSX3gR6e?= =?us-ascii?Q?LXKcn+Fk2D6v6uf0owIyEpBDKzCXNNkKlfOplXJD7I78uN251+l/4KRZbDV4?= =?us-ascii?Q?VC3ekjb0ET/hs/ETa04VhoVGGTuOBs9EB0viANhV7QCclMJ2RP70oTo/ySnD?= =?us-ascii?Q?UyzL16K+lCHpLy6KnA7WOk7myWGn2w872BSqBT6lbQWwAdUuFhCW/mIZxXkD?= =?us-ascii?Q?aHAi7LPZ2GHY30eZbSWG2YyTgBXolbuQBDyWlrGxra0dpOBsRY5aIwXPph3u?= =?us-ascii?Q?M3hcDrp7XBjkPyeaueEs2BUFfvmfZnQEg847Wlqbe2QWDM3RPoC1PGHnzKpt?= =?us-ascii?Q?/E3B7B6fE4vShteFtFySv/mR5e78pydy6dlyc0rvOClY/K9Atr0QXJxws9Uh?= =?us-ascii?Q?RBNxaEzBKZOGcfDPUqlZiPVB+a4WkR9tVQASiO072FkxLemZdiFGxoTZ5/XL?= =?us-ascii?Q?3ep6s5SDm69wRPq/KpfGd4SyPxzwTSTJ65667r5peGCUmSdSrJegZOogwFCA?= =?us-ascii?Q?bL3ey7+p5VpMa3+oGQd8wruIQlR8PX5Tmpd46QfVzhxfv5YTrXhunKbFzhZO?= =?us-ascii?Q?+ORlxaSx8DuOkCSQ6JOlK+rpd5Zr/aT6bq2XO0A+xk+dr6h6mHTPIsUb0Ba7?= =?us-ascii?Q?hASmrGZBJ+Yz9y9sekurvDHP+3+WT4gF6OYe80bzPjvXJxwrOcXAW0eVhlBl?= =?us-ascii?Q?MIk7XstZuj8qPWjqzcYzkde4AbmRw6pnLCIX6lTKViKmk29dxQlN3DS0Nic4?= =?us-ascii?Q?yBH9mRFgEtzGe+VbJQS4sCFtjNpg5Jo7Xok56YYIYIF3gg2tWCYlDBLIwtPS?= =?us-ascii?Q?BjddUK9zHiYo5OwYs6ukon6HM/ubFasl3RJc9wpQ631Ar6fmei/9GxDhcaMS?= =?us-ascii?Q?nZtXb+MQxbVt+DweGbOu8cClr2OjauWTWlEHhbfj7mAMGbv8R+EdbFfPlU1h?= =?us-ascii?Q?SysghU6TUunBigsYnjs1XQ3/FwkJm32lyxevA2jmvSkLGZF9wvTGkQF13Maa?= =?us-ascii?Q?HouAIwU8PPnf5xKke5aogbMEfyEOowGRxDKN9iR8nE/Rs4nIWlBMZwNuvPtu?= =?us-ascii?Q?2ZPbElPvkuHRmtyBswzUf0JZ3FeR2CKnn4lpl3mLD4EoSCeuevnmWr/LYQHK?= =?us-ascii?Q?nyg1SQTFKr7oxPt8sv/hm6l4x9UpgtrXocfyg4tpklBDinzsMkBd3ViazkLO?= =?us-ascii?Q?XuZmQy9EfznyFUStLHpG7lr6V32jIzjQHbkQDvy6qBEcvdrOHfHjW6/AXic6?= =?us-ascii?Q?cm6U3Vw2RHqiVeBduCcYFcdJ6H2i85FM2/k0SQpnIxDnY6Zcrsgas9pPWmJ3?= =?us-ascii?Q?4FmsWwSQbIbgx4Z+G+hR4eeF9FESAofr1cX0+Dm7xknDbs8e0u3eB+gcsZoO?= =?us-ascii?Q?0f6Pv/QeJvaf2BMhwTKL/TdhKKJ/Z09hIa9AM8dSY1WQJAMxmjNxK4mC/JAs?= =?us-ascii?Q?vu26/xOtRQPcN3L7DWyUgCf50rVmAOjmZZJ8ZARKMHj3KkM5NlKwjqO6DV77?= =?us-ascii?Q?9vdc1etf8ZozpPf3kvFM/NMKI/SpLZ6W16sJFD+ysAcbQNC/6sUsgSFmvEW9?= =?us-ascii?Q?sPp/rkUVFUz3DGY6d4Q=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fec849dc-1ee6-4528-8aba-08ddd82fa0dd X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Aug 2025 17:02:03.3537 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: ATcPNo+pa28eZCR8JftR0i9jgCDxmwcDt/C1JwNANqcLcmzpVdD0nFciBdhhfL3Z X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB5596 On Sat, Aug 09, 2025 at 12:53:09PM -0400, Demi Marie Obenour wrote: > > With a long term goal that struct page only exists for legacy code, > > and is maybe entirely compiled out of modern server kernels. > > Why just server kernels? I suspect client systems actually run > newer kernels than servers do. I would guess this is because of the people who are interested in this work. Frankly there isn't much benifit for small memory client systems. Modern servers have > 1TB of memory and struct page really hurts here. The flip side of this is the work is enormous and I think there is a general idea that the smaller set of server related drivers and subsystems will get ready well before the wider universe of stuff a client or android might use. It is not that more can't happen it just ultimately depends on interest and time. Many modern servers use quite new kernels if you ignore the enterprise distros :\ Jason