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Wysocki" , Danilo Krummrich , Jonathan Corbet , Shuah Khan , Laurent Pinchart , Wolfram Sang , Johan Hovold , "Paul E . McKenney" Subject: Re: [PATCH v10 8/9] platform/chrome: Protect cros_ec_device lifecycle with revocable Message-ID: <20260514160214.GH787748@nvidia.com> References: <20260508105448.31799-1-tzungbi@kernel.org> <20260508105448.31799-9-tzungbi@kernel.org> <20260508115309.GA9254@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: CH0PR13CA0011.namprd13.prod.outlook.com (2603:10b6:610:b1::16) To LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) 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: LV8PR12MB9620:EE_|IA0PPFDDA81179A:EE_ X-MS-Office365-Filtering-Correlation-Id: 39a60b19-d517-4021-a8ca-08deb1d22afb X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|7416014|376014|56012099003|4143699003|11063799003|18002099003|22082099003; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?+z8E5SI5rMbwBAXeZduuXdS0f+kRopqFaGMRrcUpl31gr5bviyZqbQyP9YQP?= =?us-ascii?Q?OojJzCDtuWW8t7nQ/ZVUhCbD6MZvJHpBFQLxvLhtzLlznX9ltzPPk4Mr/ks6?= =?us-ascii?Q?UlZUyaUJuB8WMHRRw6WH25TYU1pm7aLKqAfSzk2OA4ucX1AYOFQ0eZpCzqon?= =?us-ascii?Q?KqQ2IAp9JTp40xSf6WWRcFvOkZ9/AzJMvvsUreEzD86R4Id6FUaZfcnSSjMI?= =?us-ascii?Q?JpqFsgfVPh1KbDLijXbQvBKRmJoXWHl2GPdnNCwGRYeHzE6ier5N2NfpeUUO?= =?us-ascii?Q?2S3zaCazu/NQkBB7AY63kPoH58AfqoWymaVnl+eMeTp091Uj7Jye+n1mL2XW?= =?us-ascii?Q?Q0R3bg95FtnuMtSscIVd4xw8LxOsj7qpyuiTCISFdNHu0s3Ur5uHucfaVcY4?= =?us-ascii?Q?kY5aJSSRtYxJIY+7hz6GH4eLZNq74F1BDjxkXnaWbOFXCAJ8RLgmxckWURrn?= =?us-ascii?Q?0TMfAG/UJHBXhgA6RrXD1g6QX/BsQIccU2galjJtmG4Hx/EIS8gdQ8trGQMQ?= =?us-ascii?Q?PbRj7ZrFEvhb9q1f6LmtBQam/KPf3GHa71ppzozk3Pux9AGjmq18658bYz4H?= =?us-ascii?Q?Nc1FC9VopITGksNK/w2fKcR791qzYOjp1ZS6Y67hDbOne3C91fz6pEB0imGI?= =?us-ascii?Q?5cHcgn1SEdabMwnPiwZ3/qMqJ77EaNv2wPx4whgvd/fbTrxLZ9n9d7T+5lGl?= =?us-ascii?Q?9pbW6PpDYkze23fTVAYRX1QQWspeknFjwcm00degsBayF+fKTEortYeYSXjN?= =?us-ascii?Q?fPPQ/K3vSxUmrVCLuZfUzXzp/NIzDhBGvIAiP9rgUUAyWxM0rC5fhSaNMEnM?= =?us-ascii?Q?3Rn22SZM2ZGI8pVgNO7/GUPjRivVf+XRMPAFH95QT757Y2Eji8IL0M/kCMsk?= =?us-ascii?Q?3wex1EXpJFqMRm1jLmWP0TBEBD2ZawqlgRrC+gmmU9vbCwS8cgDwQYVEGNiA?= =?us-ascii?Q?zm+LaIaMFGTt8MwpLjqYBwAKfuNW7iBus6WGglf0/ON35+t2ISLFquPvGTkc?= =?us-ascii?Q?8rrRLHaFi5Le7wscELRmlE90QFocbhbcaIIL+6mg1deaNr8/gc0NoUjgy3Py?= =?us-ascii?Q?MBRPm/kL2b3u9MPjIay7Zl5GwGJhBwPfUqRormcd9qQUrl9ti4fNF81Lq4ri?= =?us-ascii?Q?MD2FADQmEhTT6zThTCE2vHQoJLZeGlVKNl+cd5Ex61s4QQrriY6xuSHZPCIR?= =?us-ascii?Q?DzbRa5Nmb3MoHXLN0Eyipi71VobmbJPl6aI/1yV9eUqOZKb2zh8Wpw9A0/2m?= =?us-ascii?Q?TqyRRkb7lGI0z+wqMIazXNQ/0w6nxwqzynXlZn6MoVrBXI/Z8BMflLSMmi43?= =?us-ascii?Q?MA4/AgAoq6PW/a7M6vaHkZiCPAzRnoEBCXclpfyA9v67lBkQgsT90/ln/hCo?= =?us-ascii?Q?1mpnXA8RFwVrg2Q5kDEuVmpSJUJu2HUw1a8mOhk2eeknNEAEetU5B9er5VBA?= =?us-ascii?Q?2eTFsrvXckp1fzKs9yG8JN6ydmOptxvNa647bZsw23mo32oP+zA77U54otGB?= =?us-ascii?Q?kZvTlte5eU/nPMCbIPtfr6Mr/U35d3hEWSpEIEmtz8olQPaBfiZTnYmYaRXf?= =?us-ascii?Q?aLDeoPUgIKRfuN6GUrFwdkhdI86z5F9NE0Hm6GHuYZIWgxq9get1a4rtzSeF?= =?us-ascii?Q?B5FiHrK8PDzc0ruwdRX82a+aY9wm8hs7QwaP8aDJOnW3O4FeywXtaipwG3dy?= =?us-ascii?Q?NvPoUnKc2h7qeKIgekb2cAQtj3zEwV0l78UazrXBPjGG7oHr?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 39a60b19-d517-4021-a8ca-08deb1d22afb X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 May 2026 16:02:15.6923 (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: YcO0kJLnTIxonZx1/42onrG//obC2BD59GUfnSqsqcBFnyRRZjNg1qqVe7fPvmBp X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPFDDA81179A On Thu, May 14, 2026 at 03:33:55AM +0000, Tzung-Bi Shih wrote: > > Given you say this is such a bug I think you really should be sending > > a series that is patches 5 through 7 from the other series and a > > simple rwsem instead of misc_deregister_sync() to deal with this bug > > ASAP. No need to complicate a simple bug fix in a driver with all > > these core changes. > > Apologies for missing this suggestion. > > For "patches 5 through 7 from the other series" I guess you're referring: > - https://lore.kernel.org/all/20260427134659.95181-6-tzungbi@kernel.org > - https://lore.kernel.org/all/20260427134659.95181-7-tzungbi@kernel.org > - https://lore.kernel.org/all/20260427134659.95181-8-tzungbi@kernel.org Yes > Could you provide a bit more detail on the rwsem approach? I'm not > entirely clear on what data or operations the rwsem would be protecting. Just put a rwsem, or even scru, inside the driver's fops. You can refactor that out to a misc or revocable later. Jason