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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?eVF6dXc+dUlX/0quwdBLIhINoLbOl3PxCqm4Av3iOD3PpImnTuamHQhdHo4L?= =?us-ascii?Q?EKS7PPTzwcG3iY+wQs02p9zpc89EOpmruSJT4AmCEagCzS3wCbufi8PuAN8j?= =?us-ascii?Q?/XHLxLH3uAAz3GPmWwAFm5ENeOjAdApcm30nKyYO0qJvca/7n/rXNOvsYVEv?= =?us-ascii?Q?ul5TmJSqyuRe8N/8jeB5O7Me9tiyBAEz8f2XdSBU7En5ULYqu63iU4VYkuB5?= =?us-ascii?Q?ZOmO25AD7li8uSeWIIsRRVgsI33H2LJCjPQLCmYrrJffexsLTLSmYruEadsD?= =?us-ascii?Q?eoQ0oTlg6W+vJs0GqlRDo7sdc397Z5A7IPG9YhRkPsk6QwP4qtaNCAGM8n1Z?= =?us-ascii?Q?sUa6nuauWd/cb31duK9/VadFW3/2eQlUwqcAj03BxdUrGCsAAc4pM9gHX9eV?= =?us-ascii?Q?otXnbgCkZYvR2ksZSWfQdVK6c3dUPqyzggi3G2fnVubL7hCgHi0SO8dE6A37?= =?us-ascii?Q?rwAKh78nt+Gi0VxKc49qX0tNlXPwzF7kTj1IJL1eWuxTHdIdiDScT8Ap+xWF?= =?us-ascii?Q?+QdY4SIp9xTX6Vk7qn3CVSsPee5bjTWkr+ZpyFem33l7cX+fyhg9TY4AU1MT?= =?us-ascii?Q?V5UAjZSKEYRWB210KOxOnZ20IR796PxEZe92QLKNWJTqTmDkggwKxJt2cc5z?= =?us-ascii?Q?AAHcAeVUc4O0jLWP4reqyYncxEAdjUXcR7OKvyC6VCH9IyLbLWX/prPSOvEW?= =?us-ascii?Q?w5CuJMf//LpOuhb0v6wEsKbwD1b/P7tk5uUTh8k7RDOzfczssloT5Z1MTIlA?= =?us-ascii?Q?HDH77d2h0UAF4iIaXyEfv4JNl5y23KOvV/cmBaPqyeGtMswWdW+TrmSQ9qlX?= =?us-ascii?Q?U7lzeRAXvpnvNMYOO2d0KEMynHK9ChNGCJFCBXKDYHM0HbwxnGi2LGHMGRc7?= =?us-ascii?Q?pM3wllYoaxpxSf4txeM9pDGoNE15sbc/z5JXHMv9iJPmzMngNnG47ocBfx98?= =?us-ascii?Q?w84IIiaunbtgxIUhhT//ZYaHLKoWSv8ISE0JpLkdg+JnmUPPKLOUUxXDDh+q?= =?us-ascii?Q?ha3DIAF4ZfK2uCnYqFjiG8F/PO70IkNh7meiYRoENfwxIJ2VPwYOGOGd9kQ1?= =?us-ascii?Q?cJCdPQ1RrBGW3XHIiJWK7JYkFYSMLFFUGKmuw4ZfBoWJTKeRV1s5PL/X0//A?= =?us-ascii?Q?+v0WuLy1at4gjsSlNQOU3t/JzvdCOlj4QU/9z2kMNhTcrxnoz+FIP1rCPov3?= =?us-ascii?Q?Yn93jg319Ke1qUH9MFTbeccTfM3DUx/qK1SJccQusk3AaX1T14gmG+tvW2Ln?= =?us-ascii?Q?p+rjqDdwGqeRkC+MhKynaTeLZQP0xZxKg5P/fKyj3EFwlLDhm80m0R1QevXC?= =?us-ascii?Q?MnIHBgr11ugLyB0olpEci34i4hsvKDeD9cunGsBl72mpUEDupfORR4RZOeKu?= =?us-ascii?Q?9gNyGeP+psYnC+ROPMEj96YBY7od8OSLMWVJi9zFuzumrjQzZlda6TP1LCx6?= =?us-ascii?Q?vgMMosIzdZKj6YCsPu1XSi+vxjcT4gpU9MvwillumhnhQZpXq2efMKHdl2JW?= =?us-ascii?Q?6/gVuV6DpAIRp7f/tNIiFnzWUCrzBPdsh5hTT2uMA8MLD/DYOjbff0ykyMvk?= =?us-ascii?Q?wBSqOdwtYPEG6maMOyt7e7pnJQM2pzgYRXDltXZ8?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 15ad8411-05a4-49a0-b2d0-08dd58297be4 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Feb 2025 18:55:35.3559 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: SvKw/jKqxp4mY9AEa33NyM9I2+8j5QRLXrvDYxcshr15NEUO/eR53MSQmbaUn8q1 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB7719 On Thu, Feb 27, 2025 at 11:40:53PM +0100, Danilo Krummrich wrote: > On Thu, Feb 27, 2025 at 06:00:13PM -0400, Jason Gunthorpe wrote: > > On Thu, Feb 27, 2025 at 01:25:10PM -0800, Boqun Feng wrote: > > > > > > Most of the cases, it should be naturally achieved, because you already > > > bind the objects into your module or driver, otherwise they would be > > > already cancelled and freed. > > > > I'm getting the feeling you can probably naturally achieve the > > required destructors, but I think Danillo is concerned that since it > > isn't *mandatory* it isn't safe/sound. > > Of course you can "naturally" achieve the required destructors, I even explained > that in [1]. :-) > > And yes, for *device resources* it is unsound if we do not ensure that the > device resource is actually dropped at device unbind. Why not do a runtime validation then? It would be easy to have an atomic counting how many devres objects are still alive. Have remove() WARN_ON to the atomic and a dumb sleep loop until it is 0. Properly written drives never hit it. Buggy drivers will throw a warning and otherwise function safely. I'm thinking the standard design pattern is a problem that is too complex for static analysis to solve. Jason