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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH 7.2 v2 08/12] mm/huge_memory: remove folio split check for READ_ONLY_THP_FOR_FS Date: Mon, 13 Apr 2026 16:46:54 -0400 X-Mailer: MailMate (2.0r6290) Message-ID: In-Reply-To: References: <20260413192030.3275825-1-ziy@nvidia.com> <20260413192030.3275825-9-ziy@nvidia.com> Content-Type: text/plain X-ClientProxiedBy: MN0P222CA0017.NAMP222.PROD.OUTLOOK.COM (2603:10b6:208:531::22) To DS7PR12MB9473.namprd12.prod.outlook.com (2603:10b6:8:252::5) 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: DS7PR12MB9473:EE_|CH3PR12MB8727:EE_ X-MS-Office365-Filtering-Correlation-Id: b16c8b50-d26b-4b46-5b94-08de999dcf03 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|7416014|376014|22082099003|56012099003|18002099003; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?B7zkXrNe9C+GNWNnhsImn0Cpdg/xB4lCpI8pq7QHuIsi83wwGpgECdC39sZW?= =?us-ascii?Q?PkMGzPZyYTsWbJpKr7mGerokhdeRBGw7+mSjNk8DC/v4FqZmejwCOCUO4f/J?= =?us-ascii?Q?JW0M9b2UTcwUZmwPrzmHBZRKlJ4ExzrghjmH3z/fM4vywaUUDiV2EwyrJAG6?= =?us-ascii?Q?9vcb7cHtnj/ITylJ0EJaqtNEfWBt/osfSP3vuM/SM+ApD56mqRtWq23Hmcug?= =?us-ascii?Q?cskOn0yFyxjYEVCWRoygNZZeW7fONiPgV237B/wNJr88YdAdCPbrvlByCamQ?= =?us-ascii?Q?0FY070OPFB2k6bHgY7mr0fIvMa2paUk0M9yk2uiw9g6z24uHXUS3BEfJd7e5?= =?us-ascii?Q?MW91UlJRkTda7/mGOCEr2YVBSjYTfi7XaRuQALP4OiBEEZNhtpDyhwNYMK8H?= =?us-ascii?Q?O0ugVHVXFDGMbG//bCL4NF1cfurWuIfajaIR/m4Rbdm4huLERUlvkHYCznKm?= =?us-ascii?Q?TwGe9v89vGZ4PzhWB+vxz22/iI5wcUH0cgasHilYl8MswohcoUk338xCiAtg?= =?us-ascii?Q?llp9DRT31lgGKTpy9i+HbjfQUi0Ot7HGtlY5sIs9ufZQmM8F2cqTl94v/SyH?= =?us-ascii?Q?HbkADqE6hFp2OQSvFzbVn4sM4l4RLWTAJthGpahQEZkzfgdqvHFqxjvdFLzm?= =?us-ascii?Q?NuO2HB4JaNLYebh1yYEZqRhfYNKC1Ij4tfCpOQPOm0S8wXDMfslXZTk5bWoT?= =?us-ascii?Q?DMvp3CgdbtPk8pmQsZZyXLOt9zI2Fs7jatC2o/WpYOhLXUSZI9pTtTGJmMEo?= =?us-ascii?Q?YrjwysGiKcRhkjzObWQdi2R0nJfzVuE2RjfF1rm3v7khA0OY2nT/HjjFyV5b?= =?us-ascii?Q?Nxd6LClea2Bsnc6gna9swNhXFLW6XtyDmXZnJk3HVStCKU8yKjoAodiJDYRC?= =?us-ascii?Q?X7pNFkVxHnTuuVaSURRH8qnGVkbLtdQ/aJzIoaVTtgH4tVf0DCfMQuq/4leB?= =?us-ascii?Q?oaB1d6BxyUEwHToE9NEwUi0plZi8w2xWVKF3LdNOE224LPH+YAUH3WNzDVVJ?= =?us-ascii?Q?SW6v9GNFoFbG9tr6O9Ic/Oql4jpr7vTzdjAiEZoCLnvnheh5PepHxrilRgVF?= =?us-ascii?Q?vDWqZl7Sls0qng8LLltOtxl5rtn69NarlOfP2ibuBEkzmRl8ny7PLLOvpbaC?= =?us-ascii?Q?7XXF9Zz82NdWxrxRfcCEsBu35xx9Pu6q6XR6Lx3gVPOD4e6xEBepOSwJnTZY?= =?us-ascii?Q?q4pJyxhxiKMe6iHFnVbhdd59ufi4IWjwnqIFrvP3P98Ti59+s6iTKcIWxvp/?= =?us-ascii?Q?T8KhY7OwP2iRl8DYaY+jDUVVyBwwY+zw/MxXGam2tMFWPP2rnpyYnAll/8/Z?= =?us-ascii?Q?0BBGE3TAxSOdRoB6wqqXyRklN9hCpneKQtISfA+GvUhtctfk9LKNTTE7j5yR?= =?us-ascii?Q?5sMezJ2KYez2+Qces0PB0PphtQtv33Nu2PTmhUWxtgKxErjDa7+d0QEbYu3R?= =?us-ascii?Q?AnF6Uh0nBuGwWj0jKE9yUWS0X22zwRXNPNJtY2Y7AP6VV7nXUlLhlI0WSL1M?= =?us-ascii?Q?+snIzky62/2wAW2TbzkygfV0R8rxeUnbUxHhqTN2safRPnESy24SzvtT949a?= =?us-ascii?Q?x3UKqyVkS3TkZQnhJ8LqKEFArlbsDS0rBjx61xsOogdtVjvotaKRupmmKue8?= =?us-ascii?Q?ZeQucCzpxCp9jI6pUvAVutLmhcPg2CodVeuf/zXYhJQI8fsPy24hE2G7a+sz?= =?us-ascii?Q?Wwg0fqLicIieTRxA83exca8Si3ZzChl4AR1evHewDy2CgOpwVNIFFA1JH827?= =?us-ascii?Q?xFATTQwbdA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b16c8b50-d26b-4b46-5b94-08de999dcf03 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Apr 2026 20:46:59.6258 (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: G7iiL21lLdXMBdyWOwrGrFvPn7ibD4tPt8VZ9LnjRyHIF76DTGbFZf+WOPxOWudp X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8727 On 13 Apr 2026, at 16:41, Matthew Wilcox wrote: > On Mon, Apr 13, 2026 at 03:20:26PM -0400, Zi Yan wrote: >> + /* order-1 is not supported for anonymous THP. */ > > It's also not supported for file folios, right? Or do we just skip > adding order-1 file folios to the deferred split list? Either way, order <= 1 folios are not added to deferred split list. See deferred_split_folio(). IIUC, we have order-1 file folios but not order-1 anon folios. > we need to correct _something_, whether it's the code or the comment. > >> + if (folio_test_anon(folio) && new_order == 1) >> + return -EINVAL; Best Regards, Yan, Zi