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>

drivers/acpi/dispatcher/dsopcode.c

@@ -808,6 +808,12 @@ acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
 
 	/* The first operand (for all of these data objects) is the length */
 
+	/*
+	 * Set proper index into operand stack for acpi_ds_obj_stack_push
+	 * invoked inside acpi_ds_create_operand.
+	 */
+	walk_state->operand_index = walk_state->num_operands;
+
 	status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
@@ -1070,8 +1076,7 @@ acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
 			 * is set to anything other than zero!
 			 */
 			walk_state->return_desc = walk_state->operands[0];
-		} else if ((walk_state->results) &&
-			   (walk_state->results->results.num_results > 0)) {
+		} else if (walk_state->result_count) {
 
 			/* Since we have a real Return(), delete any implicit return */
 

drivers/acpi/dispatcher/dsutils.c

@@ -630,9 +630,7 @@ acpi_ds_create_operand(struct acpi_walk_state *walk_state,
 			 * Use value that was already previously returned
 			 * by the evaluation of this argument
 			 */
-			status =
-			    acpi_ds_result_pop_from_bottom(&obj_desc,
-							   walk_state);
+			status = acpi_ds_result_pop(&obj_desc, walk_state);
 			if (ACPI_FAILURE(status)) {
 				/*
 				 * Only error is underflow, and this indicates
@@ -698,27 +696,54 @@ acpi_ds_create_operands(struct acpi_walk_state *walk_state,
 {
 	acpi_status status = AE_OK;
 	union acpi_parse_object *arg;
-	u32 arg_count = 0;
+	union acpi_parse_object *arguments[ACPI_OBJ_NUM_OPERANDS];
+	u8 arg_count = 0;
+	u8 count = 0;
+	u8 index = walk_state->num_operands;
+	u8 i;
 
 	ACPI_FUNCTION_TRACE_PTR(ds_create_operands, first_arg);
 
-	/* For all arguments in the list... */
+	/* Get all arguments in the list */
 
 	arg = first_arg;
 	while (arg) {
-		status = acpi_ds_create_operand(walk_state, arg, arg_count);
-		if (ACPI_FAILURE(status)) {
-			goto cleanup;
+		if (index >= ACPI_OBJ_NUM_OPERANDS) {
+			return_ACPI_STATUS(AE_BAD_DATA);
 		}
 
-		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
-				  "Arg #%d (%p) done, Arg1=%p\n", arg_count,
-				  arg, first_arg));
+		arguments[index] = arg;
+		walk_state->operands[index] = NULL;
 
 		/* Move on to next argument, if any */
 
 		arg = arg->common.next;
 		arg_count++;
+		index++;
+	}
+
+	index--;
+
+	/* It is the appropriate order to get objects from the Result stack */
+
+	for (i = 0; i < arg_count; i++) {
+		arg = arguments[index];
+
+		/* Force the filling of the operand stack in inverse order */
+
+		walk_state->operand_index = index;
+
+		status = acpi_ds_create_operand(walk_state, arg, index);
+		if (ACPI_FAILURE(status)) {
+			goto cleanup;
+		}
+
+		count++;
+		index--;
+
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+				  "Arg #%d (%p) done, Arg1=%p\n", index, arg,
+				  first_arg));
 	}
 
 	return_ACPI_STATUS(status);
@@ -729,9 +754,8 @@ acpi_ds_create_operands(struct acpi_walk_state *walk_state,
 	 * pop everything off of the operand stack and delete those
 	 * objects
 	 */
-	(void)acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
+	acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
 
-	ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %d",
-			(arg_count + 1)));
+	ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %d", index));
 	return_ACPI_STATUS(status);
 }

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;