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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" , "Shivam Kalra" To: , From: "Zi Yan" X-Mailer: aerc 0.21.0 References: <20260813-swap-thp-cleanup-v2-0-d2ee48c6aa49@tencent.com> <20260813-swap-thp-cleanup-v2-2-d2ee48c6aa49@tencent.com> In-Reply-To: <20260813-swap-thp-cleanup-v2-2-d2ee48c6aa49@tencent.com> X-ClientProxiedBy: YQBPR0101CA0173.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:c01:f::16) 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_|CH3PR12MB8880:EE_ X-MS-Office365-Filtering-Correlation-Id: edf0227f-405d-4666-8f0a-08defa74723c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|1800799024|23010399003|366016|6133799003|11063799006|10067099003|56012099006|4143699003|18002099003|22082099003; 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It > rejects the split and returns -EINVAL without unfreezing the folio or > restoring the counters. That error path is buggy: if it is ever taken, > it leaves the folio frozen and stuck, skews the counters, and fires > the VM_WARN_ON_ONCE_FOLIO for a state that is actually legitimate. > > Check for this case up front in folio_check_splittable and return > -EBUSY before any state is modified, so the split routine always backs > out cleanly. > > Also fix a bracket style issue that checkpatch.pl keeps complaining > about. > > Fixes: 00527733d0dc ("mm/huge_memory: add two new (not yet used) function= s for folio_split()") > Fixes: 714b056c8321 ("mm/huge_memory: convert VM_BUG* to VM_WARN* in __fo= lio_split") > Signed-off-by: Kairui Song > --- > mm/huge_memory.c | 27 ++++++++++++++++----------- > 1 file changed, 16 insertions(+), 11 deletions(-) > The handling is an improvement. Thanks. Reviewed-by: Zi Yan --=20 Best Regards, Yan, Zi