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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) 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-Mailman-Approved-At: Mon, 08 Sep 2025 23:53:50 -0700 X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org 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