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charset=UTF-8 Date: Tue, 30 Jun 2026 18:48:39 -0400 Message-Id: Subject: Re: Subject: [BUG/RFC] write-open file THP cache purge can discard dirty page cache Cc: "Alexander Viro" , "Christian Brauner" , "Jan Kara" , "Matthew Wilcox" , "Andrew Morton" , "Song Liu" , , , , "Eric Hagberg" , "David Hildenbrand" , "Lorenzo Stoakes" To: "Pedro Falcato" , "Gregg Leventhal" From: "Zi Yan" X-Mailer: aerc 0.21.0 References: In-Reply-To: X-ClientProxiedBy: CH0PR03CA0417.namprd03.prod.outlook.com (2603:10b6:610:11b::6) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::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: IA0PR12MB8374:EE_|DM4PR12MB6352:EE_ X-MS-Office365-Filtering-Correlation-Id: 54a2a9b4-db0d-479a-09e6-08ded6f9bb2e X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|7416014|1800799024|23010399003|22082099003|18002099003|5023799004|56012099006|4143699003|11063799006; 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And it avoids any weird forward-progress issues as no one c= an >> write to folios at that point. >>=20 > > Gregg, if you could test this patch, it would be much appreciated. This p= atch > (hopefully) makes it so no dirty folio will ever coexist with a ro-THP, t= hus > hopefully sidestepping the entire issue in a simple way. Only compile-tes= ted > and not reviewed. I tested the patch on v6.12 kernel with the reproducer from Gregg and confirmed that the issue is fixed. Feel free to add Tested-by: Zi Yan --=20 Best Regards, Yan, Zi