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> > + struct device *dev = mds->cxlds.dev; > > + unsigned int extent_gen_num; > > + int rc; > > + > > + if (!cxl_dcd_supported(mds)) { > > + dev_dbg(dev, "DCD unsupported\n"); > > + return 0; > > + } > > + > > + rc = cxl_dev_get_dc_extent_cnt(mds, &extent_gen_num); > > + dev_dbg(mds->cxlds.dev, "Extent count: %d Generation Num: %d\n", > > + rc, extent_gen_num); > > + if (rc <= 0) /* 0 == no records found */ > > + return rc; > > + > > + return cxl_dev_get_dc_extents(cxled, extent_gen_num, rc); > > Not sure about the behaviour here. From the cxl_dev_get_dc_extents > implementation below, if gen_num changed or the expected extent count > changed, it will return error. yep. > If I understand it correctly, if the above two values change, it means > the extent list has been updated due to extent add/release since last > time we read the extent list info (cxl_dev_get_dc_extent_cnt), do we > need to fail the operation or try again? The original series was safe to fail the operation because the list was read on memory device driver load and not when the regions were created. This is an oversight with the new architecture. Now that regions query for the list independent of other regions being active the list could indeed change during this operation. :-/ So a retry is necessary. Let me work on the retry because some of the extents may have been surfaced during the list processing which means a re-read of the list will need to properly ignore those already found. Or some other tracking needs to be put in place. Ira