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Thu, 31 Oct 2024 00:06:28 +0000 Message-ID: <9e0645cd-9162-44fa-8fa6-971bb08fa755@intel.com> Date: Wed, 30 Oct 2024 17:06:25 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 14/16] x86/cpu: Make LAM depend on LASS To: Alexander Shishkin , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H. Peter Anvin" , Peter Zijlstra , Ard Biesheuvel , "Paul E. McKenney" , Josh Poimboeuf , Xiongwei Song , Xin Li , "Mike Rapoport (IBM)" , Brijesh Singh , Michael Roth , Tony Luck , "Kirill A. Shutemov" , Alexey Kardashevskiy CC: Jonathan Corbet , Ingo Molnar , "Pawan Gupta" , Daniel Sneddon , Kai Huang , "Sandipan Das" , Breno Leitao , Rick Edgecombe , Alexei Starovoitov , Hou Tao , Juergen Gross , Vegard Nossum , Kees Cook , Eric Biggers , Jason Gunthorpe , "Masami Hiramatsu (Google)" , Andrew Morton , Luis Chamberlain , Yuntao Wang , "Rasmus Villemoes" , Christophe Leroy , Tejun Heo , Changbin Du , Huang Shijie , "Geert Uytterhoeven" , Namhyung Kim , Arnaldo Carvalho de Melo , , , References: <20241028160917.1380714-1-alexander.shishkin@linux.intel.com> <20241028160917.1380714-15-alexander.shishkin@linux.intel.com> Content-Language: en-US From: Sohil Mehta In-Reply-To: <20241028160917.1380714-15-alexander.shishkin@linux.intel.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BYAPR08CA0066.namprd08.prod.outlook.com (2603:10b6:a03:117::43) To BYAPR11MB3320.namprd11.prod.outlook.com (2603:10b6:a03:18::25) Precedence: bulk X-Mailing-List: linux-efi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BYAPR11MB3320:EE_|CY5PR11MB6137:EE_ X-MS-Office365-Filtering-Correlation-Id: 4d9eb171-8772-4c85-bc7c-08dcf93fddcb X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|1800799024|376014|366016|921020; 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If the system is missing LASS at boot then LAM would still be enabled. We would need this patch to enforce it: https://lore.kernel.org/lkml/20241030233118.615493-1-sohil.mehta@intel.com/ Sohil