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Howlett" , "Nico Pache" , "Ryan Roberts" , "Dev Jain" , "Barry Song" , "Lance Yang" , "Usama Arif" , "Vlastimil Babka" , "Mike Rapoport" , "Suren Baghdasaryan" , "Michal Hocko" , "Shuah Khan" , "Kevin Brodsky" , , , To: "Yeoreum Yun" From: "Zi Yan" Subject: Re: [PATCH 1/2] kselftest: mm: prevent random failure of huge page split for khugepaged X-Mailer: aerc 0.22.0 References: <20260820-fix_split-v1-0-ab430c58c7cf@arm.com> <20260820-fix_split-v1-1-ab430c58c7cf@arm.com> In-Reply-To: X-ClientProxiedBy: YQBPR01CA0151.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:c01:7e::9) 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_|BL4PR12MB9480:EE_ X-MS-Office365-Filtering-Correlation-Id: dc053419-792a-413c-78c3-08deff1400df X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|7416014|23010399003|366016|6133799003|56012099006|10067099003|4143699003|11063799006|22082099003|18002099003; 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No. I did not realize there is no way of stopping khugepaged completely. BTW, I am curious about your khugepaged config causing this issue. IIRC, khugepaged scan interval is about minutes and the time between madvise(MADV_HUGEPAGE) and the second is_backed_by_folio() should not be that long. For your patch, maybe you want to check the return value of madvise() to make sure it succeeds. Otherwise, feel free to add Reviewed-by: Zi Yan Thanks. --=20 Best Regards, Yan, Zi