libnvdimm/region: Fix label activation vs errors

BugLink: https://bugs.launchpad.net/bugs/1943756

commit d9cee9f upstream.

There are a few scenarios where init_active_labels() can return without
registering deactivate_labels() to run when the region is disabled. In
particular label error injection creates scenarios where a DIMM is
disabled, but labels on other DIMMs in the region become activated.

Arrange for init_active_labels() to always register deactivate_labels().

Reported-by: Krzysztof Kensicki <krzysztof.kensicki@intel.com>
Cc: <stable@vger.kernel.org>
Fixes: bf9bccc ("libnvdimm: pmem label sets and namespace instantiation.")
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Link: https://lore.kernel.org/r/162766356450.3223041.1183118139023841447.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: djbw

drivers/nvdimm/namespace_devs.c

@@ -2527,7 +2527,7 @@ static void deactivate_labels(void *region)
 
 static int init_active_labels(struct nd_region *nd_region)
 {
-	int i;
+	int i, rc = 0;
 
 	for (i = 0; i < nd_region->ndr_mappings; i++) {
 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
@@ -2546,13 +2546,14 @@ static int init_active_labels(struct nd_region *nd_region)
 			else if (test_bit(NDD_LABELING, &nvdimm->flags))
 				/* fail, labels needed to disambiguate dpa */;
 			else
-				return 0;
+				continue;
 
 			dev_err(&nd_region->dev, "%s: is %s, failing probe\n",
 					dev_name(&nd_mapping->nvdimm->dev),
 					test_bit(NDD_LOCKED, &nvdimm->flags)
 					? "locked" : "disabled");
-			return -ENXIO;
+			rc = -ENXIO;
+			goto out;
 		}
 		nd_mapping->ndd = ndd;
 		atomic_inc(&nvdimm->busy);
@@ -2586,13 +2587,17 @@ static int init_active_labels(struct nd_region *nd_region)
 			break;
 	}
 
-	if (i < nd_region->ndr_mappings) {
+	if (i < nd_region->ndr_mappings)
+		rc = -ENOMEM;
+
+out:
+	if (rc) {
 		deactivate_labels(nd_region);
-		return -ENOMEM;
+		return rc;
 	}
 
 	return devm_add_action_or_reset(&nd_region->dev, deactivate_labels,
-			nd_region);
+					nd_region);
 }
 
 int nd_region_register_namespaces(struct nd_region *nd_region, int *err)