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Wysocki" , "Danilo Krummrich" , "Miguel Ojeda" , "Boqun Feng" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Benno Lossin" , "Andreas Hindborg" , "Alice Ryhl" , "Trevor Gross" , "Daniel Almeida" , "Tamir Duberstein" , =?utf-8?q?Onur_=C3=96zkan?= , "Matthew Maurer" , , , Subject: Re: [PATCH] samples: rust: debugfs: fix excessive stack use From: "Gary Guo" To: "Alexandre Courbot" , "Gary Guo" X-Mailer: aerc 0.21.0 References: <20260716144144.3665719-1-gary@kernel.org> In-Reply-To: X-ClientProxiedBy: LO4P265CA0051.GBRP265.PROD.OUTLOOK.COM (2603:10a6:600:2ac::13) To LOVP265MB8871.GBRP265.PROD.OUTLOOK.COM (2603:10a6:600:488::16) Precedence: bulk X-Mailing-List: driver-core@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LOVP265MB8871:EE_|CWXP265MB2055:EE_ X-MS-Office365-Filtering-Correlation-Id: 94787852-c212-4e90-908a-08dee37e844f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|10070799003|23010399003|376014|7416014|3023799007|10067099003|56012099006|18002099003|4143699003|22082099003; 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>> } >> - let blob =3D KBox::pin_init(new_mutex!([0x42; SZ_4K]), GFP_KERNEL)?= ; >> + let blob =3D KBox::pin_init(new_mutex!(pin_init::init_array_from_fn= (|_| 0x42)), GFP_KERNEL)?; > > Since this is a sample, do we want to specify the size explicitly as it > is arguably more readable in this case? It's not easy to specify size with `init_array_from_fn` because you need to specify additionally Init, T and E, so it'll become init_array_from_fn::<_, SZ_4K, _, _> which is ugly. Best, Gary