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Miller" , Andreas Larsson , Arnd Bergmann , Greg Kroah-Hartman , Dan Williams , Vishal Verma , Dave Jiang , Nicolas Pitre , Muchun Song , Oscar Salvador , David Hildenbrand , Konstantin Komarov , Baoquan He , Vivek Goyal , Dave Young , Tony Luck , Reinette Chatre , Dave Martin , James Morse , Alexander Viro , Christian Brauner , Jan Kara , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Hugh Dickins , Baolin Wang , Uladzislau Rezki , Dmitry Vyukov , Andrey Konovalov , Jann Horn , Pedro Falcato , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-csky@vger.kernel.org, linux-mips@vger.kernel.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-mm@kvack.org, ntfs3@lists.linux.dev, kexec@lists.infradead.org, kasan-dev@googlegroups.com Subject: Re: [PATCH 16/16] kcov: update kcov to use mmap_prepare, mmap_complete Message-ID: <20250908133013.GD616306@nvidia.com> References: <65136c2b1b3647c31bc123a7227263a99112fd44.1757329751.git.lorenzo.stoakes@oracle.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <65136c2b1b3647c31bc123a7227263a99112fd44.1757329751.git.lorenzo.stoakes@oracle.com> X-ClientProxiedBy: YT4P288CA0037.CANP288.PROD.OUTLOOK.COM (2603:10b6:b01:d3::19) To PH7PR12MB5757.namprd12.prod.outlook.com (2603:10b6:510:1d0::13) Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB5757:EE_|CH1PPFC8B3B7859:EE_ X-MS-Office365-Filtering-Correlation-Id: bf7383e5-907e-4c0f-a384-08ddeedbd866 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7416014; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?r/zKPyCfBe/6J+m5XEar+lXDZ9bJMlJC54ZIXcfnDRn0pfldDdCZzorCWOPM?= =?us-ascii?Q?f/ugf78Fkt5y+MtRJ1Y+/eIfrhbyXvi1Z42zXaw5vZkExLO9isYis5zRctaS?= =?us-ascii?Q?zxFTTwIkXpzOKAucI63xu3IL0rHEh4o6NdpZ7A1C3pHdEu/AA3ce5JmetZHf?= =?us-ascii?Q?Uzu4VwtCc8zAtXjwKrUO/x+5tPAanTQslp9vfeNcg5fltwvGF1SDRvJvRePp?= =?us-ascii?Q?xTAvsRWZJzW0GfRff1FonvAI2HjSfTf3vY/8hxLVXz8viy9VPjG2EpGSiBEL?= =?us-ascii?Q?bHpNCqzG6MoMbZQsduYUZmd20m6GUfkZIGo10tFkHfEbYX5GQTZpkpKQjU2V?= =?us-ascii?Q?wWTK6Vm14w23Lmcx+dRwm+AZ+Up7nHOYt0d2tFRkpHwUWVWVIShbCSyzQYBR?= =?us-ascii?Q?J217cStGMlEpgX4oMr0WZ2Kf+eMn0HWn5bZabRmKyDCUMjXnMxrEd9C0Ro+E?= =?us-ascii?Q?QMl/sDAw91eTxwp70Sz5JRQ7hkDeL8oDeirB7n2FCW3ntwtvZriHvxp/5ckh?= =?us-ascii?Q?xY3UGWuRGZz10kl4mQFTTu3XM99HihRR4c4jMozo9UC0mAwvwAgsJboOZNRr?= =?us-ascii?Q?WkDy+dRNfENvP0d9KeFlTBJlosSe+kAlJlvZWk3Llc+DIvIO1zR500ie4t63?= =?us-ascii?Q?cWjxd8InLIp3tDmkWhZjeVizk6KdSGxXSMahJyUtr1sFiMBgcLxTS9wToPZ4?= =?us-ascii?Q?2UhJW85tTN+d4XCCRhu69WlQkXgOujC6VrbOLXZLkukyuO9FXpoC158v/Z1q?= =?us-ascii?Q?kppvV7ZycvSvzoUHKSanGXbyNVm1W6eFnrE8aeFLyq42Isk4yp7PrDTId99Y?= =?us-ascii?Q?D0aMJxkXOLQ8/QWlv8mXT+Z1oftVi5+Uc0eDBmEea+e/WaE9J36hOHAa2DGI?= =?us-ascii?Q?G8WF3fdXpCaK5HcK94vdhM5CCnd97KWp7lBYL0Z58/RfzTZ4rhvUMKWD3ZPP?= =?us-ascii?Q?O9yDJMxzZtql/uC5duHKBixFQIB+Qtv85Fj1OkuVBKpEX3mEof2/Rab+p5jj?= =?us-ascii?Q?sgn3x1hQyR9TM9CNN8MPd/1QRWKpD0lfxfLqtdOwTi3f6BoM4vFDgon5HVfe?= =?us-ascii?Q?76GakdjugnnPq3J9NAMlv3YYrLYhyWZXaLKmM48IGVUwEiJgblLVehYQONEz?= =?us-ascii?Q?twoLRvCyChCMMIsghtTTGTb6OAIQkcSPaL1Ia5CRnNyGj7Oeq42SSaB/s/1w?= =?us-ascii?Q?LSWz5qecHeqUB/I4toKcPOrsi0JFY2wMYNAxKG/xf+AV3SkmKq8gXcTw0aIw?= =?us-ascii?Q?vsSFN775aJlxReo5qpjuwO+97Nw6bARD+5qp0nrt33yQ5cXoZ00VZq5A6AhO?= =?us-ascii?Q?ivW7flb4FDmww7dHpQ0SJgUtixK9ilrgZVAn2Jq2BDpyVnWotiBXlfiIU4aG?= =?us-ascii?Q?E+/YPyiazMWRPO8DoI92aIUrqwvkSK9uyBs3yis3s/Ghy2wZN/D71VZBLhnl?= =?us-ascii?Q?jm36AByUCFGFAWRvDCkHC1bVNhsiRF8xvkcy47315xq5zvf0M8wxyZZtWUxf?= =?us-ascii?Q?A4twvvouLMQshWrvMkruBWRNtnj5EXD9scZfk9unmTEV4zsvl1J08cKHca8Y?= =?us-ascii?Q?Bou1BiARRjtvykVK7w4=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bf7383e5-907e-4c0f-a384-08ddeedbd866 X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Sep 2025 13:30:15.4185 (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: kIPAyt1SIUharTVbKnH+ode+hdhgODYC87gyhtAj+SIGuOMjQ96I3qN3TO5FXcek X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH1PPFC8B3B7859 On Mon, Sep 08, 2025 at 12:10:47PM +0100, Lorenzo Stoakes wrote: > Now we have the capacity to set up the VMA in f_op->mmap_prepare and then > later, once the VMA is established, insert a mixed mapping in > f_op->mmap_complete, do so for kcov. > > We utilise the context desc->mmap_context field to pass context between > mmap_prepare and mmap_complete to conveniently provide the size over which > the mapping is performed. Why? + vma_desc_size(desc) != size) { + res = -EINVAL; Just call some vma_size()? Jason