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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 08/16] mm: add remap_pfn_range_prepare(), remap_pfn_range_complete() Message-ID: <20250908133538.GF616306@nvidia.com> References: <895d7744c693aa8744fd08e0098d16332dfb359c.1757329751.git.lorenzo.stoakes@oracle.com> <20250908130015.GZ616306@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: YT4PR01CA0235.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:eb::23) 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: 2b1abce0-3b27-4a91-4505-08ddeedc99ad 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?XoSFbBmQ/CennDI8oGI0MESDwwJX8yEwaHfHkpFzoNPSkfzfCDLpJgtLTrI0?= =?us-ascii?Q?SUpq83zu7SxOXaU+/wiNK014JpLYDaKvfTdbUYX2Ye+0+ytFyeT67llbsWJ/?= =?us-ascii?Q?bU8WHlxGrTd/eQ1LSF1LZiNzUB9wIluTBs33OCAJyp8rgDBnHxg3vo/8jIoC?= =?us-ascii?Q?6J0AL32mUTblgy5BaelXuS1eaWbaIW5MG4YiVEadeqrVevgfByWLS1hsKqDz?= =?us-ascii?Q?5J4oUYF7LTBAANzNZDBxoU+L/64ddHSo3bKBvnNwoT+/hvW58W4XYU0vbVi6?= =?us-ascii?Q?LznekYaA4157apt1Z4sBrC5AjXojFR/K5SWsGpL5n7EG/duNHMRS9z8IJLH0?= =?us-ascii?Q?yb9MNom4HdZs23t8nEhLy4zTV5hSUv/ezS+vu8bNKBPmuqHPhKajLbdu+NYL?= =?us-ascii?Q?XFNq6FCYdzZfHBViB9h32hMZl5Za7PJ6Ux0nI6ngfUuQ4HH3KoauI0KDqh3h?= =?us-ascii?Q?bRWZQYh9k5xhnh4ncGaCeXerBnmE3GLaHsGT3t2cGI5y3TPsl19PNs9fwXtw?= =?us-ascii?Q?MGW9mz8KEoWpj3dA3YTTM7R/jvXow20E7MogxHij7kjL477kylqJYn1frt1y?= =?us-ascii?Q?jRVV5HdchogiipTpKEU1xKHxpsXdrvZ5WC6ZRqAEiFqaVDTg+d75efEq03A4?= =?us-ascii?Q?HUel/xTJN9UdPUitqyJcnupLu/Nvo90cF/stAC2Ixm9AwTeUnf3/rPiFmmpL?= =?us-ascii?Q?hUnb9kYvxOVslrUT0boTzxcvvih1yEvm5hUmFUbSbLOAvct0jHiGlwwsqTEd?= =?us-ascii?Q?zIR4k2JA+OibLbooYWuMDWyEUf6NswxR5eTne2gExobaEm1e9Zcxo8OSAaxV?= =?us-ascii?Q?tvUQXZ9+1+YVzftXOs/Pnh9boONC5y14i0wDVWzs1IW5a72z0A5ribvDwb5M?= =?us-ascii?Q?0G9TijqNGBjsZtCj+Flzcs3zVqIWlLagQ0wfbjjsWbRemHOgmkA9w+v/rw1S?= =?us-ascii?Q?BbzaEvA1/bfTpNoU+qXVu/oHkeEtzEyyXCyF+HXqmprCux+RuyAqjxTuSqxc?= =?us-ascii?Q?o603eA8jGFqDyMB4wMyzWmv2C5rstnentmJVWEhSAok4EWFMi5ZpvTAgoj8t?= =?us-ascii?Q?jLHaKXPkCmAnsoeyBUPfBx53Og5Fg4YchUI8iq9sZ5li5m0VhOrizP/6tTgy?= =?us-ascii?Q?oxhmRGajUcPCEaYJELT2L4FwzSq6SGoz6LudOOJVGFSWxepbuHKzZsFu6xmp?= =?us-ascii?Q?knvYA+tHJAGMSgKQNucWWyd/d9PPWNYbQviMILNzikJMrVc1Hvk4Snw7U3Aw?= =?us-ascii?Q?ZdsZwb5zTE95ogb4FQNlwtzsVbaetS68NbFJYi/JhoefmlgoYz8YiQ8EkM+1?= =?us-ascii?Q?xmOEFMnQYxM29LdRSbwq5aOGgQPQAbDvp4hhGnEmivNdfHhcZS+8IR9ANwuo?= =?us-ascii?Q?ww3UcqjR8PM78X5AaI1/IlvnIBz4+N8rFSC7rv6NCIwxY9VOFNFQgynE55ib?= =?us-ascii?Q?0UqYtT44c8jXInkvlUFLzHNZN9RWAYdncMIZ+kF9saqBrTZnIk2gEQzxHdlQ?= =?us-ascii?Q?eSl4eCwkfjyYgGZ0BUM4yVr+VLO8/eoSnIGiXTku+Ym/nYJI3u3pdAvF9dr8?= =?us-ascii?Q?HP/e7HFEWsuUurH1XDM=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2b1abce0-3b27-4a91-4505-08ddeedc99ad X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Sep 2025 13:35:39.6548 (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: Ywhab8dI4tMuB18SbSNhlK0aNKx8mOn9NqG+l3MsmIb9xJnhpEG9w9k3jzdq7/6h X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH1PPFC8B3B7859 On Mon, Sep 08, 2025 at 02:27:12PM +0100, Lorenzo Stoakes wrote: > It's not only remap that is a concern here, people do all kinds of weird > and wonderful things in .mmap(), sometimes in combination with remap. So it should really not be split this way, complete is a badly name prepopulate and it should only fill the PTEs, which shouldn't need more locking. The only example in this series didn't actually need to hold the lock. Jason