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McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Josh Triplett , Boqun Feng , Uladzislau Rezki , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "rcu@vger.kernel.org" References: <20261004-rcu-v1-1-3799a44367f1@gmail.com> <00F6D386-FE41-42E3-9B89-07381A49E061@nvidia.com> Content-Language: en-US From: Joel Fernandes In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: MN2PR14CA0018.namprd14.prod.outlook.com (2603:10b6:208:23e::23) To DS0PR12MB6487.namprd12.prod.outlook.com (2603:10b6:8:c4::18) 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: DS0PR12MB6487:EE_|SA3PR12MB7974:EE_ X-MS-Office365-Filtering-Correlation-Id: 6edeb3d0-ccee-44b1-d1f4-08df23f0ae45 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|1800799024|376014|23010399003|11063799006|921020|4143699003|18002099003|22082099003|6133799003|10067099003|56012099006; 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But we have no hard evidence > either way: every incident ended in a forced reset, and the dmesg was > lost. Going forward, we plan to enable the NMI and kdump to keep > investigating the cause of the RCU stalls. We will also monitor dmesg > to confirm whether transient RCU stalls actually occur. Right, I just worry that if you're not seeing recoverable/transient stalls and you start using this patch, then you might be causing side-effects that don't really help your problem and might be masking the real issue. It would be good to debug this further, and fix the right way IMO. If you show that this patch indeed helps your problem, we can consider it for 7.5, but there's little bit of time. :-) Thanks, Joel Fernandes