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Shenoy" References: <20260312044434.1974-1-kprateek.nayak@amd.com> <20260312044434.1974-7-kprateek.nayak@amd.com> <20260312094605.GY1282955@noisy.programming.kicks-ass.net> Content-Language: en-US From: K Prateek Nayak In-Reply-To: <20260312094605.GY1282955@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MWH0EPF000A6732:EE_|CH2PR12MB9517:EE_ X-MS-Office365-Filtering-Correlation-Id: 0b5775ca-17c8-4bc4-ce2a-08de801f10f7 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|82310400026|7416014|376014|1800799024|36860700016|56012099003|18002099003|22082099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(82310400026)(7416014)(376014)(1800799024)(36860700016)(56012099003)(18002099003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: /6UCeR2icpZ5zoYIye03O43twoJKqEGNu7NNO/9he/0FWygv/s8E5cPHoe0typ6OWVw3dp1lAel/4yZh3QgHSTBaatjHi/gM/aBFdvrPNGGPv9nSg8gV2Gvzm/95u+CF4fImw7JmAB5FJ6+v3q4EAJ0ZQUWkHmSKMcYZWZPaPuieOJ7aNJgp5Umw2jYpR4+4nhplbBtDdRU0hgMy9G13W7pdzML8rw5wpoFbfpIGFU4xTvTp0Bwai5HKXZtgvZMLbDE0Q/Cno20KK5R25wkK8d0oZ38jFoNOfDuAhSz/TBD4/gJ+oETrh8PSUt3vAFEXNusQjoEmVMjT95Sz5nZI3D0+uUJKlno8HZvSNfJxh8mhFCAUVQalqa5XHA/P7JzKqagpYggfIzaOWbUjN3kZD+qYcYFvvcd2QKCEPNkMXxUL16z1XZd2mxfGi4WQ/MxR X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Mar 2026 10:06:44.8812 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 0b5775ca-17c8-4bc4-ce2a-08de801f10f7 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: MWH0EPF000A6732.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB9517 Hello Peter, On 3/12/2026 3:16 PM, Peter Zijlstra wrote: >> diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h >> index 953d89d71804..c4fc7726f82a 100644 >> --- a/kernel/sched/sched.h >> +++ b/kernel/sched/sched.h >> @@ -2853,7 +2853,7 @@ static inline void idle_set_state(struct rq *rq, >> >> static inline struct cpuidle_state *idle_get_state(struct rq *rq) >> { >> - WARN_ON_ONCE(!rcu_read_lock_held()); >> + WARN_ON_ONCE(!rcu_read_lock_any_held()); > > Should we perhaps make that: > > lockdep_assert(rcu_read_lock_any_held()); > > ? That makes sense! I was under the impression this was behind CONFIG_DEBUG_LOCK_ALLOC but looks like this still checks for !preemptible() on !CONFIG_DEBUG_LOCK_ALLOC which does add a bit of overhead. I'll modify it to lockdep_assert() in the next version. -- Thanks and Regards, Prateek