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ACPICA 20050526 from Bob Moore <robert.moore@intel.com> 

Implemented support to execute Type 1 and Type 2 AML
opcodes appearing at the module level (not within a control
method.)  These opcodes are executed exactly once at the
time the table is loaded. This type of code was legal up
until the release of ACPI 2.0B (2002) and is now supported
within ACPI CA in order to provide backwards compatibility
with earlier BIOS implementations. This eliminates the
"Encountered executable code at module level" warning that
was previously generated upon detection of such code.

Fixed a problem in the interpreter where an AE_NOT_FOUND
exception could inadvertently be generated during the
lookup of namespace objects in the second pass parse of
ACPI tables and control methods. It appears that this
problem could occur during the resolution of forward
references to namespace objects.

Added the ACPI_MUTEX_DEBUG #ifdef to the
acpi_ut_release_mutex function, corresponding to the same
the deadlock detection debug code to be compiled out in
the normal case, improving mutex performance (and overall
subsystem performance) considerably.  As suggested by
Alexey Starikovskiy.

Implemented a handful of miscellaneous fixes for possible
memory leaks on error conditions and error handling
control paths. These fixes were suggested by FreeBSD and
the Coverity Prevent source code analysis tool.

Added a check for a null RSDT pointer in
acpi_get_firmware_table (tbxfroot.c) to prevent a fault
in this error case.

Signed-off-by Len Brown <len.brown@intel.com>
This commit is contained in:
Robert Moore 2005-05-26 00:00:00 -04:00 committed by Len Brown
parent 6f42ccf2fc
commit 88ac00f5a8
14 changed files with 200 additions and 93 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/acpi/dispatcher/dsmethod.c
View File

@ -139,7 +139,8 @@ acpi_ds_parse_method (
walk_state = acpi_ds_create_walk_state (owner_id, NULL, NULL, NULL);
if (!walk_state) {
return_ACPI_STATUS (AE_NO_MEMORY);
status = AE_NO_MEMORY;
goto cleanup;
}
status = acpi_ds_init_aml_walk (walk_state, op, node,
@ -147,7 +148,7 @@ acpi_ds_parse_method (
obj_desc->method.aml_length, NULL, 1);
if (ACPI_FAILURE (status)) {
acpi_ds_delete_walk_state (walk_state);
return_ACPI_STATUS (status);
goto cleanup;
}
/*
@ -161,13 +162,14 @@ acpi_ds_parse_method (
*/
status = acpi_ps_parse_aml (walk_state);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
goto cleanup;
}
ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
"**** [%4.4s] Parsed **** named_obj=%p Op=%p\n",
acpi_ut_get_node_name (obj_handle), obj_handle, op));
cleanup:
acpi_ps_delete_parse_tree (op);
return_ACPI_STATUS (status);
}

15
drivers/acpi/dispatcher/dsopcode.c
View File

@ -119,14 +119,15 @@ acpi_ds_execute_arguments (
walk_state = acpi_ds_create_walk_state (0, NULL, NULL, NULL);
if (!walk_state) {
return_ACPI_STATUS (AE_NO_MEMORY);
status = AE_NO_MEMORY;
goto cleanup;
}
status = acpi_ds_init_aml_walk (walk_state, op, NULL, aml_start,
aml_length, NULL, 1);
if (ACPI_FAILURE (status)) {
acpi_ds_delete_walk_state (walk_state);
return_ACPI_STATUS (status);
goto cleanup;
}
/* Mark this parse as a deferred opcode */
@ -138,8 +139,7 @@ acpi_ds_execute_arguments (
status = acpi_ps_parse_aml (walk_state);
if (ACPI_FAILURE (status)) {
acpi_ps_delete_parse_tree (op);
return_ACPI_STATUS (status);
goto cleanup;
}
/* Get and init the Op created above */
@ -160,7 +160,8 @@ acpi_ds_execute_arguments (
walk_state = acpi_ds_create_walk_state (0, NULL, NULL, NULL);
if (!walk_state) {
return_ACPI_STATUS (AE_NO_MEMORY);
status = AE_NO_MEMORY;
goto cleanup;
}
/* Execute the opcode and arguments */
@ -169,13 +170,15 @@ acpi_ds_execute_arguments (
aml_length, NULL, 3);
if (ACPI_FAILURE (status)) {
acpi_ds_delete_walk_state (walk_state);
return_ACPI_STATUS (status);
goto cleanup;
}
/* Mark this execution as a deferred opcode */
walk_state->deferred_node = node;
status = acpi_ps_parse_aml (walk_state);
cleanup:
acpi_ps_delete_parse_tree (op);
return_ACPI_STATUS (status);
}

56
drivers/acpi/dispatcher/dswload.c
View File

@ -145,15 +145,6 @@ acpi_ds_load1_begin_op (
if (op) {
if (!(walk_state->op_info->flags & AML_NAMED)) {
#if 0
if ((walk_state->op_info->class == AML_CLASS_EXECUTE) ||
(walk_state->op_info->class == AML_CLASS_CONTROL)) {
acpi_os_printf ("\n\n***EXECUTABLE OPCODE %s***\n\n",
walk_state->op_info->name);
*out_op = op;
return (AE_CTRL_SKIP);
}
#endif
*out_op = op;
return (AE_OK);
}
@ -486,6 +477,15 @@ acpi_ds_load2_begin_op (
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p State=%p\n", op, walk_state));
if (op) {
if ((walk_state->control_state) &&
(walk_state->control_state->common.state ==
ACPI_CONTROL_CONDITIONAL_EXECUTING)) {
/* We are executing a while loop outside of a method */
status = acpi_ds_exec_begin_op (walk_state, out_op);
return_ACPI_STATUS (status);
}
/* We only care about Namespace opcodes here */
if ((!(walk_state->op_info->flags & AML_NSOPCODE) &&
@ -493,9 +493,14 @@ acpi_ds_load2_begin_op (
(!(walk_state->op_info->flags & AML_NAMED))) {
if ((walk_state->op_info->class == AML_CLASS_EXECUTE) ||
(walk_state->op_info->class == AML_CLASS_CONTROL)) {
ACPI_REPORT_WARNING ((
"Encountered executable code at module level, [%s]\n",
acpi_ps_get_opcode_name (walk_state->opcode)));
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"Begin/EXEC: %s (fl %8.8X)\n", walk_state->op_info->name,
walk_state->op_info->flags));
/* Executing a type1 or type2 opcode outside of a method */
status = acpi_ds_exec_begin_op (walk_state, out_op);
return_ACPI_STATUS (status);
}
return_ACPI_STATUS (AE_OK);
}
@ -657,8 +662,10 @@ acpi_ds_load2_begin_op (
break;
}
/* Add new entry into namespace */
status = acpi_ns_lookup (walk_state->scope_info, buffer_ptr, object_type,
ACPI_IMODE_EXECUTE, ACPI_NS_NO_UPSEARCH,
ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH,
walk_state, &(node));
break;
}
@ -668,7 +675,6 @@ acpi_ds_load2_begin_op (
return_ACPI_STATUS (status);
}
if (!op) {
/* Create a new op */
@ -682,9 +688,7 @@ acpi_ds_load2_begin_op (
if (node) {
op->named.name = node->name.integer;
}
if (out_op) {
*out_op = op;
}
*out_op = op;
}
/*
@ -731,9 +735,24 @@ acpi_ds_load2_end_op (
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Opcode [%s] Op %p State %p\n",
walk_state->op_info->name, op, walk_state));
/* Only interested in opcodes that have namespace objects */
/* Check if opcode had an associated namespace object */
if (!(walk_state->op_info->flags & AML_NSOBJECT)) {
#ifndef ACPI_NO_METHOD_EXECUTION
/* No namespace object. Executable opcode? */
if ((walk_state->op_info->class == AML_CLASS_EXECUTE) ||
(walk_state->op_info->class == AML_CLASS_CONTROL)) {
ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
"End/EXEC: %s (fl %8.8X)\n", walk_state->op_info->name,
walk_state->op_info->flags));
/* Executing a type1 or type2 opcode outside of a method */
status = acpi_ds_exec_end_op (walk_state);
return_ACPI_STATUS (status);
}
#endif
return_ACPI_STATUS (AE_OK);
}
@ -742,7 +761,6 @@ acpi_ds_load2_end_op (
"Ending scope Op=%p State=%p\n", op, walk_state));
}
object_type = walk_state->op_info->object_type;
/*

1
drivers/acpi/dispatcher/dswstate.c
View File

@ -762,6 +762,7 @@ acpi_ds_init_aml_walk (
/* The next_op of the next_walk will be the beginning of the method */
walk_state->next_op = NULL;
walk_state->pass_number = (u8) pass_number;
if (info) {
if (info->parameter_type == ACPI_PARAM_GPE) {

29
drivers/acpi/executer/exconfig.c
View File

@ -376,16 +376,22 @@ acpi_ex_load_op (
*/
status = acpi_ex_read_data_from_field (walk_state, obj_desc, &buffer_desc);
if (ACPI_FAILURE (status)) {
goto cleanup;
return_ACPI_STATUS (status);
}
table_ptr = ACPI_CAST_PTR (struct acpi_table_header,
buffer_desc->buffer.pointer);
/* Sanity check the table length */
/* All done with the buffer_desc, delete it */
buffer_desc->buffer.pointer = NULL;
acpi_ut_remove_reference (buffer_desc);
/* Sanity check the table length */
if (table_ptr->length < sizeof (struct acpi_table_header)) {
return_ACPI_STATUS (AE_BAD_HEADER);
status = AE_BAD_HEADER;
goto cleanup;
}
break;
@ -413,7 +419,9 @@ acpi_ex_load_op (
status = acpi_ex_add_table (table_ptr, acpi_gbl_root_node, &ddb_handle);
if (ACPI_FAILURE (status)) {
goto cleanup;
/* On error, table_ptr was deallocated above */
return_ACPI_STATUS (status);
}
/* Store the ddb_handle into the Target operand */
@ -421,17 +429,14 @@ acpi_ex_load_op (
status = acpi_ex_store (ddb_handle, target, walk_state);
if (ACPI_FAILURE (status)) {
(void) acpi_ex_unload_table (ddb_handle);
/* table_ptr was deallocated above */
return_ACPI_STATUS (status);
}
return_ACPI_STATUS (status);
cleanup:
if (buffer_desc) {
acpi_ut_remove_reference (buffer_desc);
}
else {
if (ACPI_FAILURE (status)) {
ACPI_MEM_FREE (table_ptr);
}
return_ACPI_STATUS (status);

5
drivers/acpi/executer/exfield.c
View File

@ -87,6 +87,9 @@ acpi_ex_read_data_from_field (
if (!obj_desc) {
return_ACPI_STATUS (AE_AML_NO_OPERAND);
}
if (!ret_buffer_desc) {
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
if (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
/*
@ -182,7 +185,7 @@ acpi_ex_read_data_from_field (
if (ACPI_FAILURE (status)) {
acpi_ut_remove_reference (buffer_desc);
}
else if (ret_buffer_desc) {
else {
*ret_buffer_desc = buffer_desc;
}

7
drivers/acpi/executer/exnames.c
View File

@ -438,6 +438,13 @@ acpi_ex_get_name_string (
status = AE_AML_BAD_NAME;
}
if (ACPI_FAILURE (status)) {
if (name_string) {
ACPI_MEM_FREE (name_string);
}
return_ACPI_STATUS (status);
}
*out_name_string = name_string;
*out_name_length = (u32) (aml_address - in_aml_address);

11
drivers/acpi/executer/exoparg1.c
View File

@ -127,15 +127,16 @@ acpi_ex_opcode_0A_0T_1R (
cleanup:
if (!walk_state->result_obj) {
walk_state->result_obj = return_desc;
}
/* Delete return object on error */
if (ACPI_FAILURE (status)) {
if ((ACPI_FAILURE (status)) || walk_state->result_obj) {
acpi_ut_remove_reference (return_desc);
}
else {
/* Save the return value */
walk_state->result_obj = return_desc;
}
return_ACPI_STATUS (status);
}

2
drivers/acpi/namespace/nsparse.c
View File

@ -146,6 +146,7 @@ acpi_ns_parse_table (
* to service the entire parse. The second pass of the parse then
* performs another complete parse of the AML..
*/
ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "**** Start pass 1\n"));
status = acpi_ns_one_complete_parse (1, table_desc);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
@ -160,6 +161,7 @@ acpi_ns_parse_table (
* overhead of this is compensated for by the fact that the
* parse objects are all cached.
*/
ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "**** Start pass 2\n"));
status = acpi_ns_one_complete_parse (2, table_desc);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);

109
drivers/acpi/parser/psparse.c
View File

@ -66,7 +66,7 @@ static u32 acpi_gbl_depth = 0;
/* Local prototypes */
static void
static acpi_status
acpi_ps_complete_this_op (
struct acpi_walk_state *walk_state,
union acpi_parse_object *op);
@ -152,13 +152,13 @@ acpi_ps_peek_opcode (
* PARAMETERS: walk_state - Current State
* Op - Op to complete
*
* RETURN: None.
* RETURN: Status
*
* DESCRIPTION: Perform any cleanup at the completion of an Op.
*
******************************************************************************/
static void
static acpi_status
acpi_ps_complete_this_op (
struct acpi_walk_state *walk_state,
union acpi_parse_object *op)
@ -175,19 +175,26 @@ acpi_ps_complete_this_op (
/* Check for null Op, can happen if AML code is corrupt */
if (!op) {
return_VOID;
return_ACPI_STATUS (AE_OK); /* OK for now */
}
/* Delete this op and the subtree below it if asked to */
if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) != ACPI_PARSE_DELETE_TREE) ||
(walk_state->op_info->class == AML_CLASS_ARGUMENT)) {
return_VOID;
return_ACPI_STATUS (AE_OK);
}
/* Make sure that we only delete this subtree */
if (op->common.parent) {
prev = op->common.parent->common.value.arg;
if (!prev) {
/* Nothing more to do */
goto cleanup;
}
/*
* Check if we need to replace the operator and its subtree
* with a return value op (placeholder op)
@ -206,7 +213,7 @@ acpi_ps_complete_this_op (
*/
replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
if (!replacement_op) {
goto cleanup;
goto allocate_error;
}
break;
@ -223,18 +230,17 @@ acpi_ps_complete_this_op (
(op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
if (!replacement_op) {
goto cleanup;
goto allocate_error;
}
}
if ((op->common.parent->common.aml_opcode == AML_NAME_OP) &&
(walk_state->descending_callback != acpi_ds_exec_begin_op)) {
else if ((op->common.parent->common.aml_opcode == AML_NAME_OP) &&
(walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2)) {
if ((op->common.aml_opcode == AML_BUFFER_OP) ||
(op->common.aml_opcode == AML_PACKAGE_OP) ||
(op->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
replacement_op = acpi_ps_alloc_op (op->common.aml_opcode);
if (!replacement_op) {
goto cleanup;
goto allocate_error;
}
replacement_op->named.data = op->named.data;
@ -244,15 +250,15 @@ acpi_ps_complete_this_op (
break;
default:
replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
if (!replacement_op) {
goto cleanup;
goto allocate_error;
}
}
/* We must unlink this op from the parent tree */
prev = op->common.parent->common.value.arg;
if (prev == op) {
/* This op is the first in the list */
@ -298,7 +304,15 @@ acpi_ps_complete_this_op (
/* Now we can actually delete the subtree rooted at Op */
acpi_ps_delete_parse_tree (op);
return_VOID;
return_ACPI_STATUS (AE_OK);
allocate_error:
/* Always delete the subtree, even on error */
acpi_ps_delete_parse_tree (op);
return_ACPI_STATUS (AE_NO_MEMORY);
}
@ -443,6 +457,7 @@ acpi_ps_parse_loop (
struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
acpi_status status2;
union acpi_parse_object *op = NULL; /* current op */
union acpi_parse_object *arg = NULL;
union acpi_parse_object *pre_op = NULL;
@ -744,7 +759,6 @@ acpi_ps_parse_loop (
break;
default:
/*
* Op is not a constant or string, append each argument
* to the Op
@ -770,6 +784,23 @@ acpi_ps_parse_loop (
/* Special processing for certain opcodes */
if (walk_state->pass_number <= ACPI_IMODE_LOAD_PASS1) {
switch (op->common.aml_opcode) {
case AML_IF_OP:
case AML_ELSE_OP:
case AML_WHILE_OP:
/* Skip body of if/else/while in pass 1 */
parser_state->aml = parser_state->pkg_end;
walk_state->arg_count = 0;
break;
default:
break;
}
}
switch (op->common.aml_opcode) {
case AML_METHOD_OP:
@ -796,7 +827,7 @@ acpi_ps_parse_loop (
if ((op->common.parent) &&
(op->common.parent->common.aml_opcode == AML_NAME_OP) &&
(walk_state->descending_callback != acpi_ds_exec_begin_op)) {
(walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2)) {
/*
* Skip parsing of Buffers and Packages
* because we don't have enough info in the first pass
@ -900,15 +931,21 @@ acpi_ps_parse_loop (
*/
parser_state->scope->parse_scope.arg_count--;
/* Close this Op (will result in parse subtree deletion) */
/* Finished with pre_op */
acpi_ps_complete_this_op (walk_state, op);
op = NULL;
if (pre_op) {
acpi_ps_free_op (pre_op);
pre_op = NULL;
}
/* Close this Op (will result in parse subtree deletion) */
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
op = NULL;
switch (status) {
case AE_OK:
break;
@ -936,7 +973,10 @@ acpi_ps_parse_loop (
status = walk_state->ascending_callback (walk_state);
status = acpi_ps_next_parse_state (walk_state, op, status);
acpi_ps_complete_this_op (walk_state, op);
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
op = NULL;
}
status = AE_OK;
@ -962,7 +1002,10 @@ acpi_ps_parse_loop (
status = walk_state->ascending_callback (walk_state);
status = acpi_ps_next_parse_state (walk_state, op, status);
acpi_ps_complete_this_op (walk_state, op);
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
op = NULL;
status = AE_OK;
@ -976,7 +1019,10 @@ acpi_ps_parse_loop (
/* Clean up */
do {
if (op) {
acpi_ps_complete_this_op (walk_state, op);
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
}
acpi_ps_pop_scope (parser_state, &op,
&walk_state->arg_types, &walk_state->arg_count);
@ -990,7 +1036,10 @@ acpi_ps_parse_loop (
do {
if (op) {
acpi_ps_complete_this_op (walk_state, op);
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
}
acpi_ps_pop_scope (parser_state, &op,
&walk_state->arg_types, &walk_state->arg_count);
@ -1053,7 +1102,10 @@ acpi_ps_parse_loop (
/* Clean up */
do {
if (op) {
acpi_ps_complete_this_op (walk_state, op);
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
}
acpi_ps_pop_scope (parser_state, &op,
@ -1065,12 +1117,17 @@ acpi_ps_parse_loop (
}
else if (ACPI_FAILURE (status)) {
acpi_ps_complete_this_op (walk_state, op);
/* First error is most important */
(void) acpi_ps_complete_this_op (walk_state, op);
return_ACPI_STATUS (status);
}
}
acpi_ps_complete_this_op (walk_state, op);
status2 = acpi_ps_complete_this_op (walk_state, op);
if (ACPI_FAILURE (status2)) {
return_ACPI_STATUS (status2);
}
}
acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types,

6
drivers/acpi/tables/tbxfroot.c
View File

@ -331,8 +331,10 @@ acpi_get_firmware_table (
cleanup:
acpi_os_unmap_memory (rsdt_info->pointer,
(acpi_size) rsdt_info->pointer->length);
if (rsdt_info->pointer) {
acpi_os_unmap_memory (rsdt_info->pointer,
(acpi_size) rsdt_info->pointer->length);
}
ACPI_MEM_FREE (rsdt_info);
if (header) {

40
drivers/acpi/utilities/utmisc.c
View File

@ -787,7 +787,6 @@ acpi_ut_release_mutex (
acpi_mutex_handle mutex_id)
{
acpi_status status;
u32 i;
u32 this_thread_id;
@ -814,25 +813,32 @@ acpi_ut_release_mutex (
return (AE_NOT_ACQUIRED);
}
/*
* Deadlock prevention. Check if this thread owns any mutexes of value
* greater than this one. If so, the thread has violated the mutex
* ordering rule. This indicates a coding error somewhere in
* the ACPI subsystem code.
*/
for (i = mutex_id; i < MAX_MUTEX; i++) {
if (acpi_gbl_mutex_info[i].owner_id == this_thread_id) {
if (i == mutex_id) {
continue;
#ifdef ACPI_MUTEX_DEBUG
{
u32 i;
/*
* Mutex debug code, for internal debugging only.
*
* Deadlock prevention. Check if this thread owns any mutexes of value
* greater than this one. If so, the thread has violated the mutex
* ordering rule. This indicates a coding error somewhere in
* the ACPI subsystem code.
*/
for (i = mutex_id; i < MAX_MUTEX; i++) {
if (acpi_gbl_mutex_info[i].owner_id == this_thread_id) {
if (i == mutex_id) {
continue;
}
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Invalid release order: owns [%s], releasing [%s]\n",
acpi_ut_get_mutex_name (i), acpi_ut_get_mutex_name (mutex_id)));
return (AE_RELEASE_DEADLOCK);
}
ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
"Invalid release order: owns [%s], releasing [%s]\n",
acpi_ut_get_mutex_name (i), acpi_ut_get_mutex_name (mutex_id)));
return (AE_RELEASE_DEADLOCK);
}
}
#endif
/* Mark unlocked FIRST */

2
include/acpi/acconfig.h
View File

@ -64,7 +64,7 @@
/* Version string */
#define ACPI_CA_VERSION 0x20050513
#define ACPI_CA_VERSION 0x20050526
/*
* OS name, used for the _OS object. The _OS object is essentially obsolete,

2
include/acpi/acstruct.h
View File

@ -78,7 +78,7 @@ struct acpi_walk_state
u8 return_used;
u16 opcode; /* Current AML opcode */
u8 scope_depth;
u8 reserved1;
u8 pass_number; /* Parse pass during table load */
u32 arg_count; /* push for fixed or var args */
u32 aml_offset;
u32 arg_types;