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Tue, 3 Jun 2025 18:19:00 +0000 Date: Tue, 3 Jun 2025 11:18:57 -0700 From: Dan Williams To: Arnd Bergmann , Dan Williams , Arnd Bergmann , Dave Hansen CC: Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , , Greg Kroah-Hartman , Nikolay Borisov , , Kees Cook , "Naveen N Rao (AMD)" Subject: Re: [PATCH 3/3] [RFC] x86/devmem: remove low 1MB hack for x86-64 Message-ID: <683f3c91c033f_1626e10021@dwillia2-xfh.jf.intel.com.notmuch> References: <20250520152030.1499670-1-arnd@kernel.org> <20250520152030.1499670-3-arnd@kernel.org> <682e5029e88e0_1626e1008e@dwillia2-xfh.jf.intel.com.notmuch> <73120bb4-7eae-49e7-be50-1fac67d351c2@app.fastmail.com> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <73120bb4-7eae-49e7-be50-1fac67d351c2@app.fastmail.com> X-ClientProxiedBy: SJ0PR03CA0227.namprd03.prod.outlook.com (2603:10b6:a03:39f::22) To PH8PR11MB8107.namprd11.prod.outlook.com (2603:10b6:510:256::6) 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: PH8PR11MB8107:EE_|CH3PR11MB8563:EE_ X-MS-Office365-Filtering-Correlation-Id: cd677061-901d-4b6f-dcfe-08dda2cb1cfa X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|366016; 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Would that bring back the issue of conflicting > mapping flags between kernel and userspace? For the confidential VM case I expect the answer is "yes" per this patch attempt: http://lore.kernel.org/20250403120228.2344377-1-naveen@kernel.org