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Howlett" , "Nico Pache" , "Ryan Roberts" , "Dev Jain" , "Lance Yang" , "Usama Arif" , "Vlastimil Babka" , "Mike Rapoport" , "Suren Baghdasaryan" , "Michal Hocko" , "Chris Li" , "Kemeng Shi" , "Nhat Pham" , "Baoquan He" , "Barry Song" , "Youngjun Park" , "Yeoreum Yun" , "Kiryl Shutsemau (Meta)" , "Shivam Kalra" , "Kairui Song" To: , From: "Zi Yan" X-Mailer: aerc 0.22.0 References: <20260908-swap-thp-cleanup-v4-0-b532a3f20e71@tencent.com> <20260908-swap-thp-cleanup-v4-10-b532a3f20e71@tencent.com> In-Reply-To: <20260908-swap-thp-cleanup-v4-10-b532a3f20e71@tencent.com> X-ClientProxiedBy: YQBPR0101CA0335.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:c01:6b::20) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) 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: IA0PR12MB8374:EE_|CY5PR12MB9056:EE_ X-MS-Office365-Filtering-Correlation-Id: 034d8f24-1c33-4b59-020e-08df0d197ce6 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|366016|7416014|376014|1800799024|4143699003|10067099003|6133799003|18002099003|22082099003|56012099006|11063799006; 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Move it from __folio_split() into > unmap_folio(), right before the PMD split, so both the anon and file > split helpers get the early check without repeating it. > > unmap_folio() now returns -EAGAIN if the check fails and the split > helpers propagate the error. folio_split_unmapped() drops its own > copy of the check: it works on already unmapped folios and the > definitive folio_ref_freeze() in __folio_freeze_split_anon() still > catches unexpected references. > > Signed-off-by: Kairui Song > --- > mm/huge_memory.c | 29 +++++++++++++---------------- > 1 file changed, 13 insertions(+), 16 deletions(-) > LGTM. Reviewed-by: Zi Yan --=20 Best Regards, Yan, Zi