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charset=UTF-8 Date: Wed, 26 Feb 2025 17:34:01 -0800 Message-Id: To: "Greg KH" , "Jason Gunthorpe" Cc: "Danilo Krummrich" , "Joel Fernandes" , "Alexandre Courbot" , "Dave Airlie" , "Gary Guo" , "Joel Fernandes" , "Boqun Feng" , "Ben Skeggs" , , , , , Subject: Re: [RFC PATCH 0/3] gpu: nova-core: add basic timer subdevice implementation From: "John Hubbard" X-Mailer: aerc 0.20.1-0-g2ecb8770224a References: <2f062199-8d69-48a2-baa6-abb755479a16@nvidia.com> <20250225210228.GA1801922@joelnvbox> <20250225225756.GA4959@nvidia.com> <20250226004916.GB4959@nvidia.com> <20250226172120.GD28425@nvidia.com> <20250226234730.GC39591@nvidia.com> <2025022644-fleshed-petite-a944@gregkh> In-Reply-To: <2025022644-fleshed-petite-a944@gregkh> X-ClientProxiedBy: BYAPR06CA0022.namprd06.prod.outlook.com (2603:10b6:a03:d4::35) To LV2PR12MB5968.namprd12.prod.outlook.com (2603:10b6:408:14f::7) Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV2PR12MB5968:EE_|CY8PR12MB7587:EE_ X-MS-Office365-Filtering-Correlation-Id: 01c817be-f416-41a4-31ba-08dd56ced146 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|366016; 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It is quite a different scheme >> than discussed in this thread. > > And I would argue that is it the _right_ scheme to be following overall > here. Removing modules with in-flight devices/drivers is to me is odd, > and only good for developers doing work, not for real systems, right? Right...I think. I'm not experienced with misc, but I do know that the "run driver code after driver release" is very, very concerning. I'm quite new to drivers/gpu/drm, so this is the first time I've learned about this DRM behavior... > > Yes, networking did add that functionality to allow modules to be > unloaded with network connections open, and I'm guessing RDMA followed > that, but really, why? > > What is the requirement that means that you have to do this for function > pointers? I can understand the disconnect issue between devices and > drivers and open file handles (or sockets), as that is a normal thing, > but not removing code from the system, that is not normal. > I really hope that this "run after release" is something that Rust for Linux drivers, and in particular, the gpu/nova*, gpu/drm/nova* drivers, can *leave behind*. DRM may have had ${reasons} for this approach, but this nova effort is rebuilding from the ground up. So we should avoid just blindly following this aspect of the original DRM design. thanks, -- John Hubbard