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Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH] mm: Take a page reference when removing device exclusive entries Content-Language: en-US To: Matthew Wilcox , Alistair Popple CC: , Andrew Morton , "Ralph Campbell" , , References: <20230328021434.292971-1-apopple@nvidia.com> From: John Hubbard In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.126.231.37] X-ClientProxiedBy: rnnvmail201.nvidia.com (10.129.68.8) To rnnvmail201.nvidia.com (10.129.68.8) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1NAM11FT009:EE_|CH3PR12MB7594:EE_ X-MS-Office365-Filtering-Correlation-Id: d8fe3ff9-8830-489a-f7d9-08db30080857 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:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230028)(4636009)(39860400002)(346002)(396003)(136003)(376002)(451199021)(40470700004)(46966006)(36840700001)(8936002)(31686004)(2906002)(47076005)(336012)(83380400001)(426003)(2616005)(34020700004)(36860700001)(41300700001)(31696002)(86362001)(36756003)(40460700003)(7636003)(5660300002)(82740400003)(356005)(6636002)(478600001)(40480700001)(54906003)(8676002)(70586007)(70206006)(4326008)(4744005)(16526019)(82310400005)(186003)(53546011)(110136005)(316002)(26005)(16576012)(43740500002);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 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, -- John Hubbard NVIDIA