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charset=UTF-8 Date: Fri, 16 Oct 2026 16:15:20 +0900 Message-Id: Cc: "Eliot Courtney" , "Alice Ryhl" , "Burak Emir" , "Yury Norov" , "Miguel Ojeda" , "Boqun Feng" , "Gary Guo" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Benno Lossin" , "Andreas Hindborg" , "Trevor Gross" , "Danilo Krummrich" , "Daniel Almeida" , "Tamir Duberstein" , =?utf-8?q?Onur_=C3=96zkan?= , "David Airlie" , "Simona Vetter" , "Greg Kroah-Hartman" , "John Hubbard" , "Alistair Popple" , "Timur Tabi" , "Zhi Wang" , , , , , "dri-devel" Subject: Re: [PATCH v9 8/9] rust: id_pool: do not round capacity up to BitmapVec::MAX_INLINE_LEN From: "Eliot Courtney" To: "Yury Norov" , "Alexandre Courbot" X-Mailer: aerc 0.22.0-0-gc2f86b7abde3 References: <20260930-chid-v9-0-0d6cca376cff@nvidia.com> <20260930-chid-v9-8-0d6cca376cff@nvidia.com> In-Reply-To: X-ClientProxiedBy: TY6PR01CA0038.jpnprd01.prod.outlook.com (2603:1096:405:3bd::18) To DS0PR12MB6413.namprd12.prod.outlook.com (2603:10b6:8:ce::10) Precedence: bulk X-Mailing-List: nova-gpu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS0PR12MB6413:EE_|PH7PR12MB5709:EE_ X-MS-Office365-Filtering-Correlation-Id: ba498fdc-e726-4d55-b327-08df2b553ee3 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|10070799003|366016|1800799024|376014|7416014|23010399003|11063799006|4143699003|56012099006|22082099003|18002099003|10067099003|6133799003; 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So we would >> never call `bitmap_zalloc` with a value of 0, making the safety concern >> moot. > =20 > OK. Then please remove the 0-length alloc with the following re-alloc > example from the patch. use 1-bit allocation, as an extreme value, if > needed. Sure, I will update the example.