ACPICA: Object repair: Allow 0-length packages for variable-length packages

For the predefined names that return fully variable-length
packages, allow a zero-length package with no warning, since it
is technically a legal construct (and BIOS writers use it.)

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/acpi/acpica/nsprepkg.c b/drivers/acpi/acpica/nsprepkg.c
index a40155467d2e..77cdd539de16 100644
--- a/drivers/acpi/acpica/nsprepkg.c
+++ b/drivers/acpi/acpica/nsprepkg.c
@@ -112,9 +112,15 @@ acpi_ns_check_package(struct acpi_predefined_data *data,
         elements = return_object->package.elements;
         count = return_object->package.count;
 
-        /* The package must have at least one element, else invalid */
-
+        /*
+         * Most packages must have at least one element. The only exception
+         * is the variable-length package (ACPI_PTYPE1_VAR).
+         */
         if (!count) {
+                if (package->ret_info.type == ACPI_PTYPE1_VAR) {
+                        return (AE_OK);
+                }
+
                 ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
                                       "Return Package has no elements (empty)"));