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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?WgAvEZHORIrL4cWTDrhISBhz02wejbs71n0UGz6V9U6yAqk/Oe++U32cJnwI?= =?us-ascii?Q?RlBf7C24/vBwGEzPw1BJ/PUNnSaYUQtcCGy36A6RoaSwEgEC5tz4KMPOtWcg?= =?us-ascii?Q?l/HdzbqK44UxiyLlCLzEf1loE03rmh4XbxQ1Q1e00Mj9HJn3yTjQMDC0+DkZ?= =?us-ascii?Q?3+LloZXRV+9444r98zvvvICVc/0gBoLCrOgMhIUlRC3oAiRgFo/nr0V4tXuO?= =?us-ascii?Q?dRzqjcBLvnTOiVZdsZwFncSsK48C3/doiLOeI8h7AsJqEfKcrFYfRR8O3dKZ?= =?us-ascii?Q?BiCA7iZTb3narNBb+mEK4lpx92kOzMg9OGOheUAGrhiAJgbSSbdG9WBqq6fz?= =?us-ascii?Q?bNQn6Xtq9tZK7usyv20tK7QoOCF8ErMt+NCFly0Xu03x8r6APuKmc3Lsf3W7?= =?us-ascii?Q?nF5FkrHmr54XWd9nO5TxF0jj1kbM+vI6Atcm/tSs7XYTRZmLAZK3I4JNkl2F?= =?us-ascii?Q?eFYspsEDQJU0HD7L06IE08lYGznYQSLIldZPhRRPNykA4ZCzF8ox6Z4s1qzx?= =?us-ascii?Q?/DcSv65oj021Gr9Ecc+2JD4uOwM1Dmurs7RdvP/sm1IHbCxqE7a5tFsT2aWp?= =?us-ascii?Q?wsPWDVBRxnYeK2m8Xj7a7VQQv/+GRyGofuEVMsZDFYnkDlmiexDzMCo3e9af?= =?us-ascii?Q?fxdAqrLU0cZdsKnZrdxxYXTIoQRFcm18sc6QDPKGJhIZXyDrPtLnnqjm21ah?= =?us-ascii?Q?g6xYfUhwF9STlA45KSNUN4qI/n+BHIJgI8qOK7f/uaAWbR7g0z9xE4mZPSkD?= =?us-ascii?Q?NMLpVQBiQ/y06yQL0Wzeot0BtPHrDc5HcGVtQKoAmXCgRiKSAifAZ8KF4c1f?= =?us-ascii?Q?VDechIBAz+QgFMfp1dmyvDr7tE+aDtY7T3DvUw/RFscvVWrTJhSMmJp5hbak?= =?us-ascii?Q?9hxSqGmsSVN2Eiz6ip1DXNBq6eTu7i5WEhxmvJ4OdWPdnHuA8cmE70TAe57g?= =?us-ascii?Q?eNBHPDBP22B0iuQ/hSuftlDapb2yS9VHV9uo36kJpn7+rKWExTSstOPYE1c+?= =?us-ascii?Q?Z2POWlCnz+DnWp/P3NzAISI2saC2F0rhjbxttMC8hf6eJP8rS7TkqtYWxuy4?= =?us-ascii?Q?ITijI963eV2yiFl+KVGuF953qnsdSlZOXcd6OgBW7YavvTGlFxTGBQkyCgm9?= =?us-ascii?Q?pzaixGXgBok+IRMhSZaUWpf1mUlfEOmAWc8PPeqRxQIdm/VxpzXTT+czNekC?= =?us-ascii?Q?BLIv6KgMTqBLtlVWvjTBTtcp2KUytqvBEoEVXC7g8v1xHMab8nt9+n0LlE2R?= =?us-ascii?Q?Ois0pfwV5FsgecWVjTiduhTM20M8/OApw6xsvfCaw0alo9As3bOanjLtQJUZ?= =?us-ascii?Q?voK5tu3HkNnFlBxNwH8O3az7LvA6Vxig/mHDbCra30/ylotFyenCDIlq/E3V?= =?us-ascii?Q?y/DrgWPkDJVG/GhubqwBpqFCNNB4fNr5qJiSU+CgNhIm5x9kI0ZBiUf58EcK?= =?us-ascii?Q?UTaJb8CK2/9La/7cWOp6/xv2CXZFPb8W0GT1tt5H4xZHWaHm1TrAmP9/Gf7T?= =?us-ascii?Q?jTvby6XRSHrEHslYNB/DjGYz0EZbe9z74NDYBRyDAfAqU3JZH2rA9e3IAVND?= =?us-ascii?Q?i2/AqwM3s2QPC97uXHFsKP3H3LaH6q7WdG+aoQC7?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cb906428-e6a6-404f-9af8-08da9c1fe016 X-MS-Exchange-CrossTenant-AuthSource: CH2PR12MB4181.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Sep 2022 22:23:14.7904 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5icy4kyVaV/Ug1SjLrTA57yrcCDJgN9Nv49MLH33xCSkfKx3qk3XTKgo2YV2q1tD X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6249 On Wed, Sep 21, 2022 at 08:48:22AM -0700, Dan Williams wrote: > The fsdax core now manages pgmap references when servicing faults that > install new mappings, and elevates the page reference until it is > zapped. It coordinates with the VFS to make sure that all page > references are dropped before the hosting inode goes out of scope > (iput_final()). > > In order to delete the unnecessary pgmap reference taking in mm/gup.c > devdax needs to move to the same model. I think this patch is more about making devdax and fsdax use the same set of functions and logic so that when it gets to patch 16/17 devdax doesn't break. That understanding matches the first paragraph, at least. I would delete the remark about gup since it is really patch 17 that allows gup to be fixed by making it so that refcount == 0 means not to look at the pgmap (instead of refcount == 1 as is now) ? Jason