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charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.126.231.35] 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: DM6NAM11FT073:EE_|PH0PR12MB7958:EE_ X-MS-Office365-Filtering-Correlation-Id: e7b43cf1-eac2-47ea-9fd7-08db8fb608ca 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:216.228.117.161;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge2.nvidia.com;CAT:NONE;SFS:(13230028)(4636009)(136003)(346002)(376002)(39860400002)(396003)(451199021)(82310400008)(36840700001)(40470700004)(46966006)(26005)(7636003)(356005)(54906003)(82740400003)(478600001)(53546011)(186003)(16526019)(336012)(426003)(47076005)(70586007)(4326008)(6916009)(2616005)(31686004)(36860700001)(70206006)(40460700003)(4744005)(5660300002)(7416002)(41300700001)(16576012)(316002)(2906002)(8936002)(8676002)(40480700001)(86362001)(31696002)(36756003)(43740500002);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Jul 2023 22:00:19.5811 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: e7b43cf1-eac2-47ea-9fd7-08db8fb608ca X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.161];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: DM6NAM11FT073.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB7958 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/28/23 14:49, Peter Xu wrote: >> The story of how FOLL_NUMA and FOLL_FORCE became entangled was enlightening, >> by the way, and now that I've read it I don't want to go back. :) > > Yeah I fully agree we should hopefully remove the NUMA / FORCE > tangling.. even if we want to revert back to the FOLL_NUMA flag we may want > to not revive that specific part. I had a feeling that we're all on the > same page there. > Yes, I think so. :) > It's more about the further step to make FOLL_NUMA opt-in for GUP. Let's say "FOLL_HONOR_NUMA_FAULT" for this next discussion, but yes. So given that our API allows passing in FOLL_ flags, I don't understand the objection to letting different callers pass in, or not pass in, that flag. It's the perfect way to clean up the whole thing. As Linus suggested slightly earlier here, there can be a comment at the call site, explaining why KVM needs FOLL_HONOR_NUMA_FAULT, and you're good, right? thanks, -- John Hubbard NVIDIA