1 files changed, 18 insertions, 5 deletions

diff --git a/drivers/acpi/acpica/dsobject.c b/drivers/acpi/acpica/dsobject.c
index 02e6caad4a76..507e1f0bbdfd 100644
--- a/drivers/acpi/acpica/dsobject.c
+++ b/drivers/acpi/acpica/dsobject.c
@@ -482,14 +482,27 @@ acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
         if (arg) {
                 /*
                  * num_elements was exhausted, but there are remaining elements in the
-                 * package_list.
+                 * package_list. Truncate the package to num_elements.
                  *
                  * Note: technically, this is an error, from ACPI spec: "It is an error
                  * for NumElements to be less than the number of elements in the
-                 * PackageList". However, for now, we just print an error message and
-                 * no exception is returned.
+                 * PackageList". However, we just print an error message and
+                 * no exception is returned. This provides Windows compatibility. Some
+                 * BIOSs will alter the num_elements on the fly, creating this type
+                 * of ill-formed package object.
                  */
                 while (arg) {
+                        /*
+                         * We must delete any package elements that were created earlier
+                         * and are not going to be used because of the package truncation.
+                         */
+                        if (arg->common.node) {
+                                acpi_ut_remove_reference(ACPI_CAST_PTR
+                                                         (union
+                                                          acpi_operand_object,
+                                                          arg->common.node));
+                                arg->common.node = NULL;
+                        }
 
                         /* Find out how many elements there really are */
 
@@ -498,7 +511,7 @@ acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
                 }
 
                 ACPI_WARNING((AE_INFO,
-                            "Package List length (%X) larger than NumElements count (%X), truncated\n",
+                            "Package List length (0x%X) larger than NumElements count (0x%X), truncated\n",
                             i, element_count));
         } else if (i < element_count) {
                 /*
@@ -506,7 +519,7 @@ acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
                  * Note: this is not an error, the package is padded out with NULLs.
                  */
                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                  "Package List length (%X) smaller than NumElements count (%X), padded with null elements\n",
+                                  "Package List length (0x%X) smaller than NumElements count (0x%X), padded with null elements\n",
                                   i, element_count));
         }