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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Subject: Re: [PATCH v15 00/11] migrate on fault for device pages Message-ID: <20260925124737.GL9354@nvidia.com> References: <20260924065313.899730-1-mpenttil@redhat.com> <65c5c412-56a7-46a9-b22b-22077a8e9727@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <65c5c412-56a7-46a9-b22b-22077a8e9727@redhat.com> X-ClientProxiedBy: PH2PEPF00003848.namprd17.prod.outlook.com (2603:10b6:518:1::65) To LY0PR12MB325698.namprd12.prod.outlook.com (2603:10b6:408:3bb::14) 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: LY0PR12MB325698:EE_|PH8PR12MB999319:EE_ X-MS-Office365-Filtering-Correlation-Id: e2eb7730-3fcc-4a33-7e03-08df1b032ef5 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|23010399003|376014|7416014|1800799024|56012099006|4143699003|10067099003|11063799006|18002099003|22082099003; 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The series seems to lack an actual user for it. > > Two users: > > For one, existing migrate_vma_setup() callers, unchanged. The series > reworks migrate_vma_setup() to collect via hmm_range_fault() internally > (it sets HMM_PFN_REQ_MIGRATE and calls migrate_hmm_range_setup(), > mm/migrate_device.c). So every in-tree migrate_vma consumer — nouveau, > amdgpu/amdkfd, drm/xe via drm_pagemap, lib/test_hmm — runs on the new path. So split the series so you don't add unused interfaces for now? Jason