diff --git a/drivers/pnp/quirks.c b/drivers/pnp/quirks.c
index 0bdf9b8..0cf4ccf 100644
--- a/drivers/pnp/quirks.c
+++ b/drivers/pnp/quirks.c
@@ -230,7 +230,8 @@ static void quirk_ad1815_mpu_resources(struct pnp_dev *dev)
 static void quirk_system_pci_resources(struct pnp_dev *dev)
 {
 	struct pci_dev *pdev = NULL;
-	struct resource *res;
+	struct resource *pci_res;
+	struct resource *pnp_res;
 	resource_size_t pnp_start, pnp_end, pci_start, pci_end;
 	int i, j;
 
@@ -247,20 +248,27 @@ static void quirk_system_pci_resources(struct pnp_dev *dev)
 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
 			unsigned int type;
 
-			type = pci_resource_flags(pdev, i) &
-					(IORESOURCE_IO | IORESOURCE_MEM);
-			if (!type || pci_resource_len(pdev, i) == 0)
+			pci_res = &pdev->resource[i];
+
+			/* skip unregistered resources */
+			if (!pci_res->parent)
+				continue;
+
+			type = pci_res->flags &
+				(IORESOURCE_IO | IORESOURCE_MEM);
+			if (!type)
 				continue;
 
-			pci_start = pci_resource_start(pdev, i);
-			pci_end = pci_resource_end(pdev, i);
+			pci_start = pci_res->start;
+			pci_end = pci_res->end;
+
 			for (j = 0;
-			     (res = pnp_get_resource(dev, type, j)); j++) {
-				if (res->start == 0 && res->end == 0)
-					continue;
+			     (pnp_res = pnp_get_resource(dev, type, j)); j++) {
+				pnp_start = pnp_res->start;
+				pnp_end = pnp_res->end;
 
-				pnp_start = res->start;
-				pnp_end = res->end;
+				if (pnp_end < pnp_start || !pnp_end)
+					continue;
 
 				/*
 				 * If the PNP region doesn't overlap the PCI
@@ -288,13 +296,13 @@ static void quirk_system_pci_resources(struct pnp_dev *dev)
 				dev_warn(&dev->dev, "%s resource "
 					"(0x%llx-0x%llx) overlaps %s BAR %d "
 					"(0x%llx-0x%llx), disabling\n",
-					pnp_resource_type_name(res),
+					pnp_resource_type_name(pnp_res),
 					(unsigned long long) pnp_start,
 					(unsigned long long) pnp_end,
 					pci_name(pdev), i,
 					(unsigned long long) pci_start,
 					(unsigned long long) pci_end);
-				res->flags |= IORESOURCE_DISABLED;
+				pnp_res->flags |= IORESOURCE_DISABLED;
 			}
 		}
 	}