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Wysocki" , Danilo Krummrich , Jonathan Corbet , Shuah Khan , Laurent Pinchart , Wolfram Sang , Johan Hovold , "Paul E . McKenney" , Dan Williams Subject: Re: [PATCH 3/8] char: misc: Introduce misc_sync_register() Message-ID: <20260508115444.GA9887@nvidia.com> References: <20260427134659.95181-1-tzungbi@kernel.org> <20260427134659.95181-4-tzungbi@kernel.org> <20260428160956.GC718365@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: SA1PR05CA0019.namprd05.prod.outlook.com (2603:10b6:806:2d2::26) To LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) 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: LV8PR12MB9620:EE_|SA0PR12MB7076:EE_ X-MS-Office365-Filtering-Correlation-Id: 6bbde9b8-513c-4496-9dfa-08deacf89940 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7416014|18002099003|56012099003|22082099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:LV8PR12MB9620.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(7416014)(18002099003)(56012099003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?cLhj2MDOhU4WcBlkjLPfdQHvoKMWeoKNpON7zljangroVkITOFEYJLE+vgCX?= =?us-ascii?Q?fES7I8O6iz1qrFcH1tb5A+0gthAuYY3x89plq5OAnyjPYMm/FfQanRvok6UZ?= =?us-ascii?Q?id/zbAwuo1COQ4wKp2kelwBdJTjSfP/jR4zJZ+CxCeils2f9cHrNF/kUrRlB?= =?us-ascii?Q?2zDGnTXexaGViTDjNSzcLq9TMpCzFf2y5ZM3Y5G4sTIL9AqdLiIKExKcavCq?= =?us-ascii?Q?X9QrbBuXOtZmaiJ19/Xe4N0d0B6+znXnvuQMO7n0pYgkPAORgWoY60gNR1Pm?= =?us-ascii?Q?vOxBboO0ZHoTIjbxo3rZhR5Ol1t4IKt2QyBSKyUyp0xoNVs7j78rzyANtAVa?= =?us-ascii?Q?ajqVaOHkbaBRvMmDAJmFyTl6t9EMp5XyzArew6tIU/k7LwkVDYzZC3G8Qcqh?= =?us-ascii?Q?YEMrXzNtwMI+GYPzkYwKYVHdO3Nu3yTtK04TrKlLCbPtMQBbI+A5gzUxysuJ?= =?us-ascii?Q?Fbs3RVHAyP4bhPgr2udeyDSJbZuDT6JRLvbItHqQMKgtlY7rat79t8R7IRrw?= =?us-ascii?Q?W5jRn0Y1HCI/18jsool2w8XijsHMSJylpCAgmj2XgqRVFTlNLsY471ABCJEs?= =?us-ascii?Q?scxH6TG3ZGbUObvnTVoVG+XqVunrk9RTOz61VTpi1KFN7v/5GStcp95wNITt?= =?us-ascii?Q?fe7IndqD+pGSeZHEvyES0ashlD0LxRRSQuh/AkCiLNB7yuPxp/mqN1R4UtSG?= =?us-ascii?Q?dSb49SqCi5dO2N4cbsMBQ6WW2y2Mj5Zz1HrHI9fcLONqEC7frM4DkcxqfOnT?= =?us-ascii?Q?xhYt+jz+l7lzRzE6ktmPVkqLE2Jh4SO2NQ1NcCErpNidOcxFeI0UNNF3MBTn?= =?us-ascii?Q?/HwUyiP4tdlkL+Dj/BE3Peq6fSP0QSUYuAU1jTbespc45X2+V7XGw4DvbxL9?= =?us-ascii?Q?gW0zabkQWJxXwQoM/SVLGArUL3jyTAlis1OJPaiH4nHhH8/AxQ5xsU+Hl0q+?= =?us-ascii?Q?XY6TcBs9JPWP11SgyDRJqkU4nwuBx2ZQe/oQdXhZ9LIigEbVVjIvr6MgFV4x?= =?us-ascii?Q?MDtct8/WPnup2jpD31RURO1reu9qa6mnt7ZMsXMJQHA5qjyVYIbIBLICrDBR?= =?us-ascii?Q?0f2zGSnRSxVhn1vwpa7kyZJfV5eM0Kmq1fCjTTx7e0k+S558rDqkb6HXjPnD?= =?us-ascii?Q?CfGbhCrmrLhOIdl7zhcN01kYU3ZfDb3/Lki56nKIHmYws2T5k+I/WxzGeJHW?= =?us-ascii?Q?mXVbKMv7t3dXiOtq9vMnUmkX00kbEbDxWT/mfiqR2xzJer+rqIBtR7g703Rp?= =?us-ascii?Q?Uhi6UYE68Fu9kVHAseHX6BZ714s91uGH4I0vcVhJvo9fgFBBm5Iwmgpl2WWY?= =?us-ascii?Q?qcWFyBplmghd8x0ZecxXDHeu5m07vTZJPvYya8LG/ShIdagTDS6c/ejKkair?= =?us-ascii?Q?XxfSOlyp/A/gzgd33HAdiBB4XRl5OsgPdMtDdw8H/1Ifo6hxZbWRvh3qNwwq?= =?us-ascii?Q?15AjjlkuOac+5eu0TNPU1eInKCP2PJlMD2sjkUegfKLSsmTLToqWJ4AiVnO6?= =?us-ascii?Q?KCy0ud5sjgFwSqzABi42EMq/5GlDF+tyVORLPki33Qgsxc7jN8j6NNrMmkB0?= =?us-ascii?Q?BMLCR7VBkfaAY2i3JkX2ztxNJ5a68KIosW1/X5hfswoWs+mMeu4LFgZV/DHw?= =?us-ascii?Q?h0auaYpdkGm2svVa1Irvo+YcpkrJkWFW7sn7kqnM7sYnnQh6/b1KIGoNB8/D?= =?us-ascii?Q?7yFcSEXDh4uoeavdqKBWfk8WAkJpNPPgK/reptOgQpkmbne5?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6bbde9b8-513c-4496-9dfa-08deacf89940 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 May 2026 11:54:45.7681 (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: jMfo6U1/GsDvVb+TIYAUrEAYGmLsi7uzkWX/+tE4qRWylLkGodwjXfNSndh1AC9D X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB7076 On Fri, May 08, 2026 at 09:38:38AM +0000, Tzung-Bi Shih wrote: > I see this as the cost for synchronizing file operations with misc driver > registration, as previously mentioned in [2], which I believe is necessary > to prevent the race conditions. I'm open to discussing potential > optimizations or alternative approaches if you have suggestions. I think the past threads had many different ideas, I don't know why you choose to present this with something that is clearly acceptable.. The drivers ops lookup needs to be O(1) on the system call path. Everything else about this series is reasonable, but you need to pick a better way to do this. Jason