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Unal" , Sergio Paracuellos , Andreas Larsson Subject: Re: [TECH TOPIC] Reaching consensus on CONFIG_HIGHMEM phaseout Message-ID: <20250919143436.GC2132010@nvidia.com> References: <4ff89b72-03ff-4447-9d21-dd6a5fe1550f@app.fastmail.com> <20250917125951.GA1390993@nvidia.com> <02b0f383-1c43-4eeb-a76f-830c2970b833@app.fastmail.com> <547dcb81-434d-4910-aa7c-1d69019fcb3d@app.fastmail.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <547dcb81-434d-4910-aa7c-1d69019fcb3d@app.fastmail.com> X-ClientProxiedBy: SA1P222CA0124.NAMP222.PROD.OUTLOOK.COM (2603:10b6:806:3c5::12) To PH7PR12MB5757.namprd12.prod.outlook.com (2603:10b6:510:1d0::13) Precedence: bulk X-Mailing-List: ksummit@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB5757:EE_|DS5PPF7B9F1F8E0:EE_ X-MS-Office365-Filtering-Correlation-Id: cb084d64-d3dc-424f-e7ba-08ddf789a94f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|7416014|376014; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?U+qH7Fd2TsJQKkFmu932eakzZFtuWMxdK367CywzPI8harCsAXQeg/zAKpSb?= =?us-ascii?Q?Azg+VKo3ldYRuoyF4sEJbKIK46XsNuY9lFlL41lPkEflK36J2F9dste6T/i7?= =?us-ascii?Q?AoGom4C3jETguK+FgzkUVsCvJ64UFebVVDwI2sSAXPGietVK8N5/R1C+2r++?= =?us-ascii?Q?iqZ/ejYsmbVepXhkPfUvqyoImNT172muOlqgITcqlTtj9YqnQCYgShKfum4a?= =?us-ascii?Q?x/HZmjpe+Dh/sXkrDKYlsUX+vjO98qQcXqhMGeu2/P+z/04ECWIpIjg2+2sk?= =?us-ascii?Q?QMitHnrRJ/eWYPNU6yOzPfbCq91WsjZ8zmXqgQAyQf0Va3nP7mv10HzFSMB8?= =?us-ascii?Q?x0VsnMOzhsYu1biuJBGY10dMkFuqGY4y5KAG+Ub7Z5Rmv504J2dyeqak3bIM?= =?us-ascii?Q?pe1JPR0nEuumGhlDKHKDtoyhpX/75Tbv74R8BH4it54pxPdi5Ay0ive3Imog?= =?us-ascii?Q?mXgiTy2BmmzTjf8nk96FURSZOS7UnyD9UGtk9KBvE5KwgwgKGHwaqv7uLElT?= =?us-ascii?Q?AP1aJPOwvYGWSK4YEggro5VL9ZMfslDBCojf/iEGwcQj1RMYZ+euH/iqLMgo?= =?us-ascii?Q?4DlQyJ8VFGUnZWNG/isENAtMNjiqP1jDZA03pKOSA0q/VzxFTDNzI7ruif6K?= =?us-ascii?Q?WncgpHUTjbYH/pFcux5Q/czZZ1caWPTB0L2ALNzu9E9wb4TUlO6JQmZM+q1I?= =?us-ascii?Q?QHknP5m/RIY8Z1hkk2DkZi4wWpRPL12ruk+TfXPmr2lETMwN0IBqgy/2k4jo?= =?us-ascii?Q?k6WsxDU8DcxWeua++v+R/jC/3XaDW6PmZ/m9gqI+EANT9aRQ+Yi47AbZubNq?= =?us-ascii?Q?ZR9XPh46uE1Rh832fMIjB2KlTUTgVwDBgBu2GhWhP1p++Wo4Jtoa/sZ6LAp3?= =?us-ascii?Q?flpUjQ5kNdGJgb9G8Xrbm23jCHZ8CGUhPfn6kP0B/rsyAQiWpZOCML0iVfZy?= =?us-ascii?Q?uzhtBEwV00/+32GbvZZ63+yzMoFNol11aGFWtz7ezr5YuD7Le8iT9ZqfJcR8?= =?us-ascii?Q?R2JrFRWxaugQvjICjRe5yPuoQXmmybgrCeUdyX5adicYYz7PZDZ/pPh7mRx5?= =?us-ascii?Q?bWgtTcKBQi4TogGF0roG8dCaUF+hERW/9zICymjQ2elZfbzJTa9wkoFr8eVV?= =?us-ascii?Q?+9ejk0nRGoHFxdtVftA0YXGR938Cvrr4LmhjeSzGuUBMvwRyGteuYCPJIL0I?= =?us-ascii?Q?+BewAHdh/dPnMu/J1DaefakWUQfLq/Gh6Nv3esWYQ++s9QFzYzpfGe+aNb3W?= =?us-ascii?Q?aHHw7MCER7wgT5ka5ijVTjyqq7w5yM6oZBEQhfTTgkdyCFUFToCRjCC1krxm?= =?us-ascii?Q?WAX6ZPpNfYmwV3vbj0SSfA7eB78U+PA3m3o2UtuJcA1WyPNbWVnSyZ8hoL2v?= =?us-ascii?Q?woGcWnSPVgGDXQJseIfxqofhuDPs7w9yXgnSr7r5H1GcEKJFuLZWvNSl7a1u?= =?us-ascii?Q?0YX07TWCLnK280eBKRXmMxa1ac/+9Ob6/BgMug6vUrJBAyjk2IJtegHr7osE?= =?us-ascii?Q?VkzbaeO5PgkcGBbzYXAwfdtrg9XXcSR37Fd35GVa05CUUkQBTyoPHSh2fVAo?= =?us-ascii?Q?ETfSNhZL82ProUr9fVK1nnUvvPJJn8mv7JlduMMP?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cb084d64-d3dc-424f-e7ba-08ddf789a94f X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Sep 2025 14:34:38.1272 (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: bLjv0KWNkTMkPQKwt0u+xmJShecgIQeR6fHB1yzmKmB0FXsQ6Q1oQTkLPlYcdApA X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS5PPF7B9F1F8E0 On Fri, Sep 19, 2025 at 04:22:20PM +0200, Arnd Bergmann wrote: > SAM9X7 in 2023 added DDR3 mode with up to 256MB according to > the datasheet, no idea why they chose not to support more, Quite possible the internal SOC wiring only has 28 address lines. :) I am right it sounds like we can drop vivt cache support with highmem? vivt is alot easier to understand if kmap isn't running around creating virtual addresses aliases! Jason