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charset=UTF-8 Date: Wed, 25 Mar 2026 20:45:17 +0900 Message-Id: Cc: "John Hubbard" , "Joel Fernandes" , "Timur Tabi" , "Alistair Popple" , "Eliot Courtney" , "Shashank Sharma" , "Zhi Wang" , "David Airlie" , "Simona Vetter" , "Bjorn Helgaas" , "Miguel Ojeda" , "Alex Gaynor" , "Boqun Feng" , "Gary Guo" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Benno Lossin" , "Andreas Hindborg" , "Alice Ryhl" , "Trevor Gross" , , "LKML" Subject: Re: [PATCH v8 05/31] gpu: nova-core: set DMA mask width based on GPU architecture From: "Alexandre Courbot" To: "Danilo Krummrich" References: <20260325035242.368661-1-jhubbard@nvidia.com> <20260325035242.368661-6-jhubbard@nvidia.com> In-Reply-To: X-ClientProxiedBy: TYCP301CA0013.JPNP301.PROD.OUTLOOK.COM (2603:1096:400:386::16) To CH2PR12MB3990.namprd12.prod.outlook.com (2603:10b6:610:28::18) 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: CH2PR12MB3990:EE_|MN0PR12MB5762:EE_ X-MS-Office365-Filtering-Correlation-Id: fab5b970-a669-4f23-acdb-08de8a63fe60 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|376014|1800799024|10070799003|7416014|18002099003|56012099003|22082099003; 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You implemented the change in = v5 and > v6 and v7 reverted it. Why? > > [1] https://lore.kernel.org/all/DGC28K8J39E2.1X173NHT9ZJDI@kernel.org/ That was on my feedback [1]. `Gpu::new` carries no guarantee in itself that no DMA ops have been performed so far; whereas in `probe` this is much clearer. [1] https://lore.kernel.org/rust-for-linux/DGYYH7GCIKJ6.2AICU9NFSKY92@nvidi= a.com/