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emacs 28.2 From: Alistair Popple To: John Hubbard Cc: Matthew Wilcox , linux-mm@kvack.org, Andrew Morton , Ralph Campbell , nouveau@lists.freedesktop.org, stable@vger.kernel.org Subject: Re: [PATCH] mm: Take a page reference when removing device exclusive entries Date: Thu, 30 Mar 2023 11:26:04 +1100 In-reply-to: Message-ID: <87zg7vt75v.fsf@nvidia.com> Content-Type: text/plain X-ClientProxiedBy: SJ0PR05CA0194.namprd05.prod.outlook.com (2603:10b6:a03:330::19) To BYAPR12MB3176.namprd12.prod.outlook.com (2603:10b6:a03:134::26) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BYAPR12MB3176:EE_|PH8PR12MB7279:EE_ X-MS-Office365-Filtering-Correlation-Id: 6595a25e-582a-4a73-ea47-08db30b5942e X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR12MB3176.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230028)(4636009)(366004)(396003)(346002)(39860400002)(136003)(376002)(451199021)(5660300002)(6862004)(83380400001)(2616005)(6506007)(26005)(6512007)(53546011)(186003)(86362001)(38100700002)(8936002)(41300700001)(36756003)(6666004)(478600001)(6486002)(66946007)(66476007)(6636002)(66556008)(8676002)(316002)(37006003)(54906003)(4326008)(4744005)(2906002);DIR:OUT;SFP:1101; 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>> From a folio point of view: what the hell are you doing here? Tail >> pages don't have individual refcounts; all the refcounts are actually I had stuck with using the page because none of this stuff (yet) supports compound pages anyway so we shouldn't see a tail page anyway. But point taken, I admit I need to find some time to get a deeper internalised understanding of folios than just s/page/folio. > ohh, and I really should have caught that too. I plead spending too much > time recently in a somewhat more driver-centric mindset, and failing to > mentally shift gears properly for this case. > > Sorry for missing that! > > thanks,