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Fri, 10 Jul 2026 02:43:37 +0000 Date: Fri, 10 Jul 2026 10:43:32 +0800 From: Yan Zhao To: "Edgecombe, Rick P" CC: "kirill.shutemov@linux.intel.com" , "linux-coco@lists.linux.dev" , "Huang, Kai" , "kvm@vger.kernel.org" , "Hansen, Dave" , "kas@kernel.org" , "seanjc@google.com" , "mingo@redhat.com" , "pbonzini@redhat.com" , "nik.borisov@suse.com" , "linux-doc@vger.kernel.org" , "hpa@zytor.com" , "Annapurve, Vishal" , "tglx@kernel.org" , "bp@alien8.de" , "linux-kernel@vger.kernel.org" , "Gao, Chao" , "x86@kernel.org" Subject: Re: [PATCH v6 07/11] KVM: TDX: Allocate PAMT memory for TD and vCPU control structures Message-ID: Reply-To: Yan Zhao References: <20260526023515.288829-1-rick.p.edgecombe@intel.com> <20260526023515.288829-8-rick.p.edgecombe@intel.com> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: TP0P295CA0028.TWNP295.PROD.OUTLOOK.COM (2603:1096:910:5::8) To PH0PR11MB7472.namprd11.prod.outlook.com (2603:10b6:510:28c::12) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH0PR11MB7472:EE_|DM6PR11MB4707:EE_ X-MS-Office365-Filtering-Correlation-Id: 21bf0b77-bdd2-46a8-5b6d-08dede2d0b05 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|376014|7416014|1800799024|23010399003|366016|56012099006|11063799006|4143699003|22082099003|18002099003; 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I > > > think it just needs a background of what is happening. How about: > > > > > > So the kernel must install PAMT backing for any 4KB page being gifting to > > > the TDX module, and tear down the backing when the associated gifted pages > > > are reclaimed. > > Hmm. I'm not sure if it would be confusing for people without sufficient > > background, because the kernel only needs to install PAMT backing before the > > gifting the first 4KB page. > > > > How about: > > So the kernel must ensure PAMT backing installed for any 4KB page being > > gifting to the TDX module, and tear down the backing when all associated > > gifted pages are reclaimed. > I see how it's better. I added a few missed word tweaks and ended up with: > > So the kernel must ensure PAMT backing is installed for any 4KB page being > gifting to the TDX module, and must tear down the backing when all associated > gifted pages are reclaimed. It's better! Thanks!