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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?/vws8Wlm3eUPV2BTtJblwM8M2yn71Tmk/3VSs2rPMCjMAy5elxlbViPePKR2?= =?us-ascii?Q?xj5RleCwylQCfEqdK+TtAnf2o6gAqTnDA7fEdPuwa8xm9LK9HDHd31bNHF/D?= =?us-ascii?Q?9tik1PDc23+wQ5MBAMZW6KueBj4e+7ff88dY3zQ2YDRO52jyOYHKQCYcSasu?= =?us-ascii?Q?WrL+f3uwQzeHYphn7i06Wd5Wmils4p6Y6HFI9hw8L93ugEJTctHp/mEHKC09?= =?us-ascii?Q?0UD1sl9IbngphfLW3vGW4lVyqyhFvFbfOBsjSb0wpeWATEXOKGOuOu6rkp48?= =?us-ascii?Q?uUFsJwxikXkcpx7RsbpZDNjTUGF8NRZesWKWbo85laxUs5qcS/dlX4vZYpU6?= =?us-ascii?Q?vRVQIniNLT5N22TEsss4ddLxPNaDK0oyj7PYFbxm434b43Q8Qn7OMb9u1/Zo?= =?us-ascii?Q?X5AiMczOZShcRlcILEXaiuN5Md4HsUIVnMrAVRe+iZD/ZdKPLn0QWaiQ4anK?= =?us-ascii?Q?t/+ZSNYNga8ia1dEIkUfCAl5YkZ7a1ZMDERo8i5pmEb8O/QTOoJfgxdUGnKS?= =?us-ascii?Q?XwvkKkfvRJNhVYujycPAQvahQOGRqhzbBYYuH5/eQbdUYzcQHz7dpF7+SNBE?= =?us-ascii?Q?R9C3mn0ssG2abZIcdX9ZIdTYutDjhiIvsNKkFFMojAot8EEJqBNPiGr7KMhw?= =?us-ascii?Q?dsgJ+/EljgaEywhLABBd0apS4aIBh7cQjUrNiNtdbyMDBdI/L9/tRA2OqRqn?= =?us-ascii?Q?ZqcuFCayU5HMoLZWYkrkWS2b1FjfWEnheTZUouvm9yc5G56QVRUpJfq5a3sk?= =?us-ascii?Q?x7qNdJpjreMBFDapwMjc2wq5oK9Wwq2s5uI6iiTeWKfY89b4no29VHahIqNb?= =?us-ascii?Q?AAxQ5NHLrAq3sttNbsFZmNOGx/7LbhYVpIRfoajWYo1/JS4/tn5V5XH8nHJb?= =?us-ascii?Q?hu0biiAzF1ulZpjR4mMLk04wUFTUw0K4DM3+KSd3+L/zaBXKw6a2+FEFZnp5?= =?us-ascii?Q?t5wQw0dlVIuaREGoue3Kun6jzyD5dbLq5yW7KnGXvYYY+xq3H57nJoNachdR?= =?us-ascii?Q?SV6MBOXG1hycwicZRRDOaYMjorZ4ZMzWUKNvHjnCLE9nVKnQWZO+f9nFQtJe?= =?us-ascii?Q?cw5zhTkk6gQ0XC2PCGp3F+25VTStKYIMxN/w+4Rv54aZRXu/AQS2nskEOFOz?= =?us-ascii?Q?PrhA3ZWcUZWnuwHfXV78v4E7jAXKzTxM0R4GZ00/46f+PGSxW8hnI4dQNFi3?= =?us-ascii?Q?IxOacucB7VozZCjdW7djGYODsmOmBL1SzCWvYr2RxQe9cbpgaIDiiVWv9nOf?= =?us-ascii?Q?zqJgFenF85FyM56X8+Z18JEPQOx+xaAAYQ/9T3hNwHk4nZwN8Q69VsWhRQqp?= =?us-ascii?Q?jPeOZowE3bzWsvlr0wkAS3+oBdKIDwtFqjpbDrIJvm/Cjj6LKZHVifcm0Qff?= =?us-ascii?Q?buV01aZ4AWQQ3Pw7TlQ0DLnuj/8EaxAdt2TGH8ksw6f4iVS4aHFMDSJpgebX?= =?us-ascii?Q?D5c8tN34paVAdIrTXFM1yNFr5lHcckUxpXsOFCmF8+324B7s9dEAE3645jVU?= =?us-ascii?Q?9WPMo6eZx6mBjdNfw9ZUyur3t0DYLGfeQOR4uFRRrcNN+dd3w5aIxEwzspZx?= =?us-ascii?Q?nyNutWw5C3n7gw2NMWf86Z/F6YDSucqzhA1/551ZH4KnqqfEldeT/YrAMDnx?= =?us-ascii?Q?n4KI13F0iMwHrRM1X+hiPAbfeYP42vUsowuEJwfONq9im0CC6modWC4MvEuy?= =?us-ascii?Q?CdZ1Hs+cAdcRDLbiek0+3vEDTB3YcEwRRyUy7CPNjop3yyPqEUdw1zcOzIQq?= =?us-ascii?Q?RTFlZrWCDKK8MoBqFB58dCIPPvw9EP0=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: d07bfe97-f7af-488c-a6c5-08da50c71c71 X-MS-Exchange-CrossTenant-AuthSource: MWHPR1101MB2126.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Jun 2022 01:08:53.4145 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: AxMlZj8QMy/9UYNhpgG8LWGv/4bp+b+WlKL0cVUCoZp/bENOQL2PAiSrNNIKXwHKr+RxDLxiLqy8qx+FRmkn2FvWME+ktS0l/PXVjETSw18= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR1101MB2200 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Alison Schofield wrote: > On Fri, Jun 17, 2022 at 11:42:11AM -0700, Dan Williams wrote: > > alison.schofield@ wrote: > > > From: Alison Schofield > > > > > > The sysfs attribute, get_poison, allows user space to request the > > > retrieval of a CXL devices poison list for its persistent memory. > > > > If the device supports get poison list for volatile memory, just grab > > that too. With the "to be released soon" region patches userspace can > > trivially translate DPA addresses to media type. > > > > Dan, > > The only way I know to discover if the device supports poison list for > volatile is to do the get_poison_list on the volatile range and see > what happens. Am I missing a capability setting somewhere? If someone executes "echo 1 > trace_poison_list" I expect that the driver does: get_poison_list(volatile_range); get_poison_list(pmem_range); ...and if scanning the volatile partition ends in error then that just means no error records appear. When the error is "Invalid Physical Address" the driver can just remember that's a permanent error and never try again. So it's more like: if (volatile_range_valid) { if (get_poison_list(volatile_range) == INVALID_PHYS_ADDR) volatile_range_valid = false; } get_poison_list(pmem_range); ...but that's probably overkill since get_poison_list() is cheap. Just treat it like the zero error records case. In the to be released region provisioning patches there is a DPA resource tree partitioned by DPA mode type, so the poison list code probably wants to do something like: down_read(&cxl_dpa_rwsem); for (p = cxlds->dpa_res.child; p; p = p->sibling) get_poison_list(p->start, resource_size(p)); up_read(&cxl_dpa_rwsem);