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To: "Dan Williams (nvidia)" , Mauro Carvalho Chehab , Dave Jiang , Smita Koralahalli , Robert Richter , Jonathan Cameron , Shiju Jose , Sathyanarayanan Kuppuswamy , "linux-cxl@vger.kernel.org" , Ben Cheatham , Lukas Wunner , "PradeepVineshReddy.Kodamati@amd.com" Cc: "linux-kernel@vger.kernel.org" References: <51a77746-5199-44a2-aa2e-d04cdd6084e7@amd.com> <6a0e33507e961_1717cc100f6@djbw-dev.notmuch> Content-Language: en-US From: "Bowman, Terry" In-Reply-To: <6a0e33507e961_1717cc100f6@djbw-dev.notmuch> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: CH2PR18CA0039.namprd18.prod.outlook.com (2603:10b6:610:55::19) To CH8PR12MB9766.namprd12.prod.outlook.com (2603:10b6:610:2b6::10) 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: CH8PR12MB9766:EE_|CYYPR12MB8653:EE_ X-MS-Office365-Filtering-Correlation-Id: 021494d5-9f21-47c4-fbfd-08deb733cefd X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|18002099003|22082099003|56012099003|3023799007|4143699003|11063799006|921020|6133799003; 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Correcting >> this will change the trace format and break the existing ABI contract >> with rasdaemon. >> >> How would you recommend proceeding to resolve this? > > Split the definitions into one that reads from the register space and > once that passes the parsed log to the trace buffer. > > Something like: > > u32 hl[CXL_HEADERLOG_TRACE_SIZE_U32]; > > ...zero-fill that and put a comment about how userspace has already > grown a dependency on the buggy size. > > In other words, keep the userspace compatibility, but fix the iomem > overflow. Ok, that's straight forward. Thanks. - Terry