diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 31122214e0ec68c92b7da6020789fcb61daed48e..1af808171d4682be716b0e7613980ed0c3fe8dc8 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -389,6 +389,17 @@ struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 
 		pbus = pdev->subordinate;
 		pci_dev_put(pdev);
+
+		/*
+		 * This function may be called for a non-PCI device that has a
+		 * PCI parent (eg. a disk under a PCI SATA controller).  In that
+		 * case pdev->subordinate will be NULL for the parent.
+		 */
+		if (!pbus) {
+			dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
+			pdev = NULL;
+			break;
+		}
 	}
 out:
 	list_for_each_entry_safe(node, tmp, &device_list, node)