cxl/pmem: debug invalid serial number data

In a nvdimm interleave-set each device with an invalid or zero
serial number may cause pmem region initialization to fail, but in
cxl case such device could still set cookies of nd_interleave_set
and create a nvdimm pmem region.

This adds the validation of serial number in cxl pmem region creation.
The event of no serial number would cause to fail to set the cookie
and pmem region.

For cxl-test to work properly, always +1 on mock device's serial
number.

Signed-off-by: Yuquan Wang <wangyuquan1236@phytium.com.cn>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://patch.msgid.link/20250219040029.515451-2-wangyuquan1236@phytium.com.cn
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Author: Yuquan Wang

drivers/cxl/pmem.c

@@ -375,15 +375,23 @@ static int cxl_pmem_region_probe(struct device *dev)
 			goto out_nvd;
 		}
 
+		if (cxlds->serial == 0) {
+			/* include missing alongside invalid in this error message. */
+			dev_err(dev, "%s: invalid or missing serial number\n",
+				dev_name(&cxlmd->dev));
+			rc = -ENXIO;
+			goto out_nvd;
+		}
+		info[i].serial = cxlds->serial;
+		info[i].offset = m->start;
+
 		m->cxl_nvd = cxl_nvd;
 		mappings[i] = (struct nd_mapping_desc) {
 			.nvdimm = nvdimm,
 			.start = m->start,
 			.size = m->size,
 			.position = i,
 		};
-		info[i].offset = m->start;
-		info[i].serial = cxlds->serial;
 	}
 	ndr_desc.num_mappings = cxlr_pmem->nr_mappings;
 	ndr_desc.mapping = mappings;

tools/testing/cxl/test/mem.c

@@ -1534,7 +1534,7 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	mds->event.buf = (struct cxl_get_event_payload *) mdata->event_buf;
 	INIT_DELAYED_WORK(&mds->security.poll_dwork, cxl_mockmem_sanitize_work);
 
-	cxlds->serial = pdev->id;
+	cxlds->serial = pdev->id + 1;
 	if (is_rcd(pdev))
 		cxlds->rcd = true;