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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Jason Gunthorpe , Peter Xu References: <20250604140544.688711-1-david@redhat.com> <1a65d0e6-6088-4a15-9c19-537203fe655c@redhat.com> <50ff9149-2824-4e57-8d74-d8d0c063c87e@lucifer.local> <1a7513cf-4a0a-4e58-b20d-31c1370b760f@lucifer.local> Content-Language: en-US From: John Hubbard In-Reply-To: <1a7513cf-4a0a-4e58-b20d-31c1370b760f@lucifer.local> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SJ0PR03CA0050.namprd03.prod.outlook.com (2603:10b6:a03:33e::25) To LV2PR12MB5968.namprd12.prod.outlook.com (2603:10b6:408:14f::7) 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: LV2PR12MB5968:EE_|BL3PR12MB6449:EE_ X-MS-Office365-Filtering-Correlation-Id: 3de083e0-bea5-41e5-e554-08dda523a4e9 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|366016|1800799024; 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And after reflecting on it a bit, I believe that, surprisingly enough, WARN_ON() is a better replacement for VM_BUG_ON() than WARN_ON_ONCE(), because: * The only time you'll be flooded with WARN_ON() messages is when *two* things happen at once: a) Something that used to completely crash the machine (a VM_BUG_ON condition) happens, and b) You're in a loop and it keeps on happening. Yes, in -mm, that does happen a lot (per-page loops, for example), but still. * It's *so* easy to miss a WARN_ON_ONCE(). We don't want that, not for a critical failure case that used to be a VM_BUG_ON(). thanks, -- John Hubbard