[PATCH 4.15 42/53] nfit: fix region registration vs block-data-window ranges

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Williams <dan.j.williams@intel.com>

commit 8d0d8ed3356aa9ed43b819aaedd39b08ca453007 upstream.

Commit 1cf03c00e7c1 "nfit: scrub and register regions in a workqueue"
mistakenly attempts to register a region per BLK aperture. There is
nothing to register for individual apertures as they belong as a set to
a BLK aperture group that are registered with a corresponding
DIMM-control-region. Filter them for registration to prevent some
needless devm_kzalloc() allocations.

Cc: <stable@vger.kernel.org>
Fixes: 1cf03c00e7c1 ("nfit: scrub and register regions in a workqueue")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/acpi/nfit/core.c |   22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -2998,15 +2998,21 @@ static void acpi_nfit_scrub(struct work_
 static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
 {
 	struct nfit_spa *nfit_spa;
-	int rc;
 
-	list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
-		if (nfit_spa_type(nfit_spa->spa) == NFIT_SPA_DCR) {
-			/* BLK regions don't need to wait for ars results */
-			rc = acpi_nfit_register_region(acpi_desc, nfit_spa);
-			if (rc)
-				return rc;
-		}
+	list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
+		int rc, type = nfit_spa_type(nfit_spa->spa);
+
+		/* PMEM and VMEM will be registered by the ARS workqueue */
+		if (type == NFIT_SPA_PM || type == NFIT_SPA_VOLATILE)
+			continue;
+		/* BLK apertures belong to BLK region registration below */
+		if (type == NFIT_SPA_BDW)
+			continue;
+		/* BLK regions don't need to wait for ARS results */
+		rc = acpi_nfit_register_region(acpi_desc, nfit_spa);
+		if (rc)
+			return rc;
+	}
 
 	acpi_desc->ars_start_flags = 0;
 	if (!acpi_desc->cancel)