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Tue, 10 Mar 2026 21:45:46 +0000 From: Dan Williams Date: Tue, 10 Mar 2026 14:45:45 -0700 To: , , , , , , , , CC: , , , , , , , , , , , , , , "Srirangan Madhavan" Message-ID: <69b0910946884_490a100ed@dwillia2-mobl4.notmuch> In-Reply-To: <20260306080026.116789-4-smadhavan@nvidia.com> References: <20260306080026.116789-1-smadhavan@nvidia.com> <20260306080026.116789-4-smadhavan@nvidia.com> Subject: Re: [PATCH 3/5] PCI: Add virtual extended cap save buffer for CXL state Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SJ0PR03CA0205.namprd03.prod.outlook.com (2603:10b6:a03:2ef::30) To PH8PR11MB8107.namprd11.prod.outlook.com (2603:10b6:510:256::6) Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH8PR11MB8107:EE_|PH7PR11MB5817:EE_ X-MS-Office365-Filtering-Correlation-Id: 9bcba7ef-bb5a-4add-33fc-08de7eee62f2 X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|1800799024|376014|18002099003|56012099003|22082099003|7053199007; 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A > virtual extended-cap save buffer API (cap IDs above > PCI_EXT_CAP_ID_MAX) allows PCI to track this state without > a backing config space capability. I think this goes away if PCI core is not tasked with understand CXL internals.