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 69693fa0722..12b148587e3 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;