ACPICA: Several fixes for internal method result stack

fixes STACK_OVERFLOW exception on nested method calls. internal
bugzilla 262 and 275.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 41 deletions

diff --git a/drivers/acpi/dispatcher/dswexec.c b/drivers/acpi/dispatcher/dswexec.c
index 69693fa07224..12b148587e3d 100644
--- a/drivers/acpi/dispatcher/dswexec.c
+++ b/drivers/acpi/dispatcher/dswexec.c
@@ -285,11 +285,6 @@ acpi_ds_exec_begin_op(struct acpi_walk_state *walk_state,
         switch (opcode_class) {
         case AML_CLASS_CONTROL:
 
-                status = acpi_ds_result_stack_push(walk_state);
-                if (ACPI_FAILURE(status)) {
-                        goto error_exit;
-                }
-
                 status = acpi_ds_exec_begin_control_op(walk_state, op);
                 break;
 
@@ -305,20 +300,11 @@ acpi_ds_exec_begin_op(struct acpi_walk_state *walk_state,
                         status = acpi_ds_load2_begin_op(walk_state, NULL);
                 }
 
-                if (op->common.aml_opcode == AML_REGION_OP) {
-                        status = acpi_ds_result_stack_push(walk_state);
-                }
                 break;
 
         case AML_CLASS_EXECUTE:
         case AML_CLASS_CREATE:
-                /*
-                 * Most operators with arguments (except create_xxx_field operators)
-                 * Start a new result/operand state
-                 */
-                if (walk_state->op_info->object_type != ACPI_TYPE_BUFFER_FIELD) {
-                        status = acpi_ds_result_stack_push(walk_state);
-                }
+
                 break;
 
         default:
@@ -374,6 +360,7 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
         /* Init the walk state */
 
         walk_state->num_operands = 0;
+        walk_state->operand_index = 0;
         walk_state->return_desc = NULL;
         walk_state->result_obj = NULL;
 
@@ -400,13 +387,6 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
                         goto cleanup;
                 }
 
-                /* Done with this result state (Now that operand stack is built) */
-
-                status = acpi_ds_result_stack_pop(walk_state);
-                if (ACPI_FAILURE(status)) {
-                        goto cleanup;
-                }
-
                 /*
                  * All opcodes require operand resolution, with the only exceptions
                  * being the object_type and size_of operators.
@@ -487,16 +467,6 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
 
                         status = acpi_ds_exec_end_control_op(walk_state, op);
 
-                        /* Make sure to properly pop the result stack */
-
-                        if (ACPI_SUCCESS(status)) {
-                                status = acpi_ds_result_stack_pop(walk_state);
-                        } else if (status == AE_CTRL_PENDING) {
-                                status = acpi_ds_result_stack_pop(walk_state);
-                                if (ACPI_SUCCESS(status)) {
-                                        status = AE_CTRL_PENDING;
-                                }
-                        }
                         break;
 
                 case AML_TYPE_METHOD_CALL:
@@ -632,13 +602,6 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
                                 break;
                         }
 
-                        /* Done with result state (Now that operand stack is built) */
-
-                        status = acpi_ds_result_stack_pop(walk_state);
-                        if (ACPI_FAILURE(status)) {
-                                goto cleanup;
-                        }
-
                         /*
                          * If a result object was returned from above, push it on the
                          * current result stack
@@ -671,8 +634,6 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
                                 if (ACPI_FAILURE(status)) {
                                         break;
                                 }
-
-                                status = acpi_ds_result_stack_pop(walk_state);
                         }
                         break;