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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/huge_memory: refactor after-split (page) cache code. 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?zhJ1qyzxhJ/jCwGpsIfLsuTuWcGd5+go6BZWNLZkTeYcvOJpVqo0LA39rhNb?= =?us-ascii?Q?aZ5T2VksE0xUv7oGpBLgDv0+imQIEMQbbdK9gqpYXYFk/0rXl1wgnoS+HORv?= =?us-ascii?Q?uEBLF7zCwx22VgcH2NQ28hoRRoHyAzokTfRvQrETMNvMOqiEUU5BAwsanxFW?= =?us-ascii?Q?fwC4E4RzrYrXsKyrM34nZhQrlBKc/Z3Jvds0NpeTS1+D5zaSxasDmb6hsFG7?= =?us-ascii?Q?DymvMhsdGuhJtG41IedoJvzRKFoHGxKRx2FQypAOvk2PvrjtK/ASJyA2ZxfP?= =?us-ascii?Q?RBwkCx5IKYJqpcDoVx8FA6F6znT7cCOfCbnrZQCs5GNgeXY289JxCqT8dv56?= =?us-ascii?Q?M41m7FOhtjUgHxed/DAVdl4Rs2b9voQ8LOrAqYPh3nQuIVAvizmrX5efrNpv?= =?us-ascii?Q?wggMwNB7WMQvtI3hGgmwncYLqdBsOFBwg1urAHll6WxNDAKnSc/9UPZJ5gyR?= =?us-ascii?Q?yML82uffpX0V/BBMGg0OLvlDVXEO1oNeM5NQsi+DSmF0INM1XEGIfjDCldtg?= =?us-ascii?Q?OS9Sy5nwFxUM7uDvEAxKT123/szzARn9mYAIM7yhj43LkPBJnI8z6xNxpp/v?= =?us-ascii?Q?rXNaSEXjxrULxsqB+V7ASx5Xe7adZMUYCr9fUQWhkuYWaGgmHZfhm+GmJrCm?= =?us-ascii?Q?CcRik/C5d9MJucWP34a/vt9PHjwRH4GoTi2taGdQmVwtd7auHxBet1leLaVO?= =?us-ascii?Q?Ivs8pVOhmjsxtJxu7rEMc1e24DNUOOcBddbm6FKRR6sbmEsA+2n/dXBWTA1H?= =?us-ascii?Q?Xr+t+aLnXT7bcH6k9dGcULGqjyJxlwEPxphL+np4wEsK4saKLRuP0ZdJ1qx+?= =?us-ascii?Q?cqWO7BpTSnvAoWecSP3NahYzB9xnb+NxfEfMsc0KfaxMH1hsBbsXpKckj8K9?= =?us-ascii?Q?Pm+6Vr0PeFznTptffWXcYk8uYXDeS5cmWxYU6CJPSH17WZKUo0UR14NBNO7U?= =?us-ascii?Q?pROLB+J0WBGjdKc0NMMyMIk+rlqxLMXdEmLGGjOgsetV8XG+VWGT4IbTY91q?= =?us-ascii?Q?s/tbhjo3k59W9te/ALVJiHiItcb7a0YdEFDNpQuWAVO50Smp9n1pLZA2NJxN?= =?us-ascii?Q?Levy0nQuqob8EVpuDad9jt119R43OCWK4NvtR+AyZmTe0rduIghPK6WIjzyO?= =?us-ascii?Q?2T+LDDTqveDa8wLAL3jhUZsjF0YHHhtyv6IeP+FHlWbCpmoOnyBsESThlpnq?= =?us-ascii?Q?Esq9J/buZAH9N5/vIJBAam4j6FzajdlQraiibGMYbeoY1xh/KirQC6FEGD9H?= =?us-ascii?Q?6CfyI8Z+I8XVcWNSPl36VcOxTfcuFnfHbbdTZXeReI/wMQCPp7upUgARBfcZ?= =?us-ascii?Q?1FEPQwUBsDOmP92FNr/tGK3zzkl1zUGLr8tROyILMZIkwJ5b+lTkJGGqznJ2?= =?us-ascii?Q?02XdWozeM9LMgXmO6piNblMNhHOL3zbJDyxMqqfexXT6TsU6DuxdXvD48k6w?= =?us-ascii?Q?WX81CrrgGktqIkS4Nq8kr0gUnB7ZeE+29F2lAFRw21lTzVIEKCQHUPncrshO?= =?us-ascii?Q?Lw4zsJpxiAcrPkynO82CKlo3Z5vzRRCbPhXzBsHBX4qWnH9jpVUHONy1W7S9?= =?us-ascii?Q?B7A7dWzpm9LulnHE407v7wte2Cw7BzciGDBUhDkz?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d063a0d1-926d-4b6b-891a-08ddc49ced14 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Jul 2025 19:14:02.9209 (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: aOY116zM0cPMaEgziIH7E1EAPCDrGbrEXclzPUCMsS7pCzxMqj2U+GxbGur9kpzh X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB8444 On 16 Jul 2025, at 15:01, Antonio Quartulli wrote: > On 16/07/2025 19:11, Zi Yan wrote: >> Smatch/coverity checkers report NULL mapping referencing issues[1][2][= 3] >> every time the code is modified, because they do not understand that >> mapping cannot be NULL when a folio is in page cache in the code. >> Refactor the code to make it explicit. >> >> No functional change is intended. >> >> [1]https://lore.kernel.org/linux-mm/2afe3d59-aca5-40f7-82a3-a6d976fb0f= 4f@stanley.mountain/ >> [2]https://lore.kernel.org/oe-kbuild/64b54034-f311-4e7d-b935-c16775dbb= 642@suswa.mountain/ >> [3]https://lore.kernel.org/linux-mm/20250716145804.4836-1-antonio@mand= elbit.com/ >> >> Suggested-by: David Hildenbrand >> Signed-off-by: Zi Yan > > Much easier to grasp - Thanks a lot! > > I am sure Coverity will be happy too at this point, because the ambigui= ty has been fully removed. > > In a previous email you asked me how to prevent Coverity from complaini= ng about certain code: my thinking is fully aligned with Dan's reply. IMH= O refactoring the code was the best choice - thanks again. Sure. Coverity/smatch makes the code better this time. :) Best Regards, Yan, Zi