cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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dswstate.c (19638B)


      1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
      2/******************************************************************************
      3 *
      4 * Module Name: dswstate - Dispatcher parse tree walk management routines
      5 *
      6 * Copyright (C) 2000 - 2022, Intel Corp.
      7 *
      8 *****************************************************************************/
      9
     10#include <acpi/acpi.h>
     11#include "accommon.h"
     12#include "acparser.h"
     13#include "acdispat.h"
     14#include "acnamesp.h"
     15
     16#define _COMPONENT          ACPI_DISPATCHER
     17ACPI_MODULE_NAME("dswstate")
     18
     19  /* Local prototypes */
     20static acpi_status
     21acpi_ds_result_stack_push(struct acpi_walk_state *walk_state);
     22static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *walk_state);
     23
     24/*******************************************************************************
     25 *
     26 * FUNCTION:    acpi_ds_result_pop
     27 *
     28 * PARAMETERS:  object              - Where to return the popped object
     29 *              walk_state          - Current Walk state
     30 *
     31 * RETURN:      Status
     32 *
     33 * DESCRIPTION: Pop an object off the top of this walk's result stack
     34 *
     35 ******************************************************************************/
     36
     37acpi_status
     38acpi_ds_result_pop(union acpi_operand_object **object,
     39		   struct acpi_walk_state *walk_state)
     40{
     41	u32 index;
     42	union acpi_generic_state *state;
     43	acpi_status status;
     44
     45	ACPI_FUNCTION_NAME(ds_result_pop);
     46
     47	state = walk_state->results;
     48
     49	/* Incorrect state of result stack */
     50
     51	if (state && !walk_state->result_count) {
     52		ACPI_ERROR((AE_INFO, "No results on result stack"));
     53		return (AE_AML_INTERNAL);
     54	}
     55
     56	if (!state && walk_state->result_count) {
     57		ACPI_ERROR((AE_INFO, "No result state for result stack"));
     58		return (AE_AML_INTERNAL);
     59	}
     60
     61	/* Empty result stack */
     62
     63	if (!state) {
     64		ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
     65			    walk_state));
     66		return (AE_AML_NO_RETURN_VALUE);
     67	}
     68
     69	/* Return object of the top element and clean that top element result stack */
     70
     71	walk_state->result_count--;
     72	index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
     73
     74	*object = state->results.obj_desc[index];
     75	if (!*object) {
     76		ACPI_ERROR((AE_INFO,
     77			    "No result objects on result stack, State=%p",
     78			    walk_state));
     79		return (AE_AML_NO_RETURN_VALUE);
     80	}
     81
     82	state->results.obj_desc[index] = NULL;
     83	if (index == 0) {
     84		status = acpi_ds_result_stack_pop(walk_state);
     85		if (ACPI_FAILURE(status)) {
     86			return (status);
     87		}
     88	}
     89
     90	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
     91			  "Obj=%p [%s] Index=%X State=%p Num=%X\n", *object,
     92			  acpi_ut_get_object_type_name(*object),
     93			  index, walk_state, walk_state->result_count));
     94
     95	return (AE_OK);
     96}
     97
     98/*******************************************************************************
     99 *
    100 * FUNCTION:    acpi_ds_result_push
    101 *
    102 * PARAMETERS:  object              - Where to return the popped object
    103 *              walk_state          - Current Walk state
    104 *
    105 * RETURN:      Status
    106 *
    107 * DESCRIPTION: Push an object onto the current result stack
    108 *
    109 ******************************************************************************/
    110
    111acpi_status
    112acpi_ds_result_push(union acpi_operand_object *object,
    113		    struct acpi_walk_state *walk_state)
    114{
    115	union acpi_generic_state *state;
    116	acpi_status status;
    117	u32 index;
    118
    119	ACPI_FUNCTION_NAME(ds_result_push);
    120
    121	if (walk_state->result_count > walk_state->result_size) {
    122		ACPI_ERROR((AE_INFO, "Result stack is full"));
    123		return (AE_AML_INTERNAL);
    124	} else if (walk_state->result_count == walk_state->result_size) {
    125
    126		/* Extend the result stack */
    127
    128		status = acpi_ds_result_stack_push(walk_state);
    129		if (ACPI_FAILURE(status)) {
    130			ACPI_ERROR((AE_INFO,
    131				    "Failed to extend the result stack"));
    132			return (status);
    133		}
    134	}
    135
    136	if (!(walk_state->result_count < walk_state->result_size)) {
    137		ACPI_ERROR((AE_INFO, "No free elements in result stack"));
    138		return (AE_AML_INTERNAL);
    139	}
    140
    141	state = walk_state->results;
    142	if (!state) {
    143		ACPI_ERROR((AE_INFO, "No result stack frame during push"));
    144		return (AE_AML_INTERNAL);
    145	}
    146
    147	if (!object) {
    148		ACPI_ERROR((AE_INFO,
    149			    "Null Object! Obj=%p State=%p Num=%u",
    150			    object, walk_state, walk_state->result_count));
    151		return (AE_BAD_PARAMETER);
    152	}
    153
    154	/* Assign the address of object to the top free element of result stack */
    155
    156	index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
    157	state->results.obj_desc[index] = object;
    158	walk_state->result_count++;
    159
    160	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
    161			  object,
    162			  acpi_ut_get_object_type_name((union
    163							acpi_operand_object *)
    164						       object), walk_state,
    165			  walk_state->result_count,
    166			  walk_state->current_result));
    167
    168	return (AE_OK);
    169}
    170
    171/*******************************************************************************
    172 *
    173 * FUNCTION:    acpi_ds_result_stack_push
    174 *
    175 * PARAMETERS:  walk_state          - Current Walk state
    176 *
    177 * RETURN:      Status
    178 *
    179 * DESCRIPTION: Push an object onto the walk_state result stack
    180 *
    181 ******************************************************************************/
    182
    183static acpi_status acpi_ds_result_stack_push(struct acpi_walk_state *walk_state)
    184{
    185	union acpi_generic_state *state;
    186
    187	ACPI_FUNCTION_NAME(ds_result_stack_push);
    188
    189	/* Check for stack overflow */
    190
    191	if (((u32) walk_state->result_size + ACPI_RESULTS_FRAME_OBJ_NUM) >
    192	    ACPI_RESULTS_OBJ_NUM_MAX) {
    193		ACPI_ERROR((AE_INFO, "Result stack overflow: State=%p Num=%u",
    194			    walk_state, walk_state->result_size));
    195		return (AE_STACK_OVERFLOW);
    196	}
    197
    198	state = acpi_ut_create_generic_state();
    199	if (!state) {
    200		return (AE_NO_MEMORY);
    201	}
    202
    203	state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
    204	acpi_ut_push_generic_state(&walk_state->results, state);
    205
    206	/* Increase the length of the result stack by the length of frame */
    207
    208	walk_state->result_size += ACPI_RESULTS_FRAME_OBJ_NUM;
    209
    210	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
    211			  state, walk_state));
    212
    213	return (AE_OK);
    214}
    215
    216/*******************************************************************************
    217 *
    218 * FUNCTION:    acpi_ds_result_stack_pop
    219 *
    220 * PARAMETERS:  walk_state          - Current Walk state
    221 *
    222 * RETURN:      Status
    223 *
    224 * DESCRIPTION: Pop an object off of the walk_state result stack
    225 *
    226 ******************************************************************************/
    227
    228static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *walk_state)
    229{
    230	union acpi_generic_state *state;
    231
    232	ACPI_FUNCTION_NAME(ds_result_stack_pop);
    233
    234	/* Check for stack underflow */
    235
    236	if (walk_state->results == NULL) {
    237		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
    238				  "Result stack underflow - State=%p\n",
    239				  walk_state));
    240		return (AE_AML_NO_OPERAND);
    241	}
    242
    243	if (walk_state->result_size < ACPI_RESULTS_FRAME_OBJ_NUM) {
    244		ACPI_ERROR((AE_INFO, "Insufficient result stack size"));
    245		return (AE_AML_INTERNAL);
    246	}
    247
    248	state = acpi_ut_pop_generic_state(&walk_state->results);
    249	acpi_ut_delete_generic_state(state);
    250
    251	/* Decrease the length of result stack by the length of frame */
    252
    253	walk_state->result_size -= ACPI_RESULTS_FRAME_OBJ_NUM;
    254
    255	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
    256			  "Result=%p RemainingResults=%X State=%p\n",
    257			  state, walk_state->result_count, walk_state));
    258
    259	return (AE_OK);
    260}
    261
    262/*******************************************************************************
    263 *
    264 * FUNCTION:    acpi_ds_obj_stack_push
    265 *
    266 * PARAMETERS:  object              - Object to push
    267 *              walk_state          - Current Walk state
    268 *
    269 * RETURN:      Status
    270 *
    271 * DESCRIPTION: Push an object onto this walk's object/operand stack
    272 *
    273 ******************************************************************************/
    274
    275acpi_status
    276acpi_ds_obj_stack_push(void *object, struct acpi_walk_state *walk_state)
    277{
    278	ACPI_FUNCTION_NAME(ds_obj_stack_push);
    279
    280	/* Check for stack overflow */
    281
    282	if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
    283		ACPI_ERROR((AE_INFO,
    284			    "Object stack overflow! Obj=%p State=%p #Ops=%u",
    285			    object, walk_state, walk_state->num_operands));
    286		return (AE_STACK_OVERFLOW);
    287	}
    288
    289	/* Put the object onto the stack */
    290
    291	walk_state->operands[walk_state->operand_index] = object;
    292	walk_state->num_operands++;
    293
    294	/* For the usual order of filling the operand stack */
    295
    296	walk_state->operand_index++;
    297
    298	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
    299			  object,
    300			  acpi_ut_get_object_type_name((union
    301							acpi_operand_object *)
    302						       object), walk_state,
    303			  walk_state->num_operands));
    304
    305	return (AE_OK);
    306}
    307
    308/*******************************************************************************
    309 *
    310 * FUNCTION:    acpi_ds_obj_stack_pop
    311 *
    312 * PARAMETERS:  pop_count           - Number of objects/entries to pop
    313 *              walk_state          - Current Walk state
    314 *
    315 * RETURN:      Status
    316 *
    317 * DESCRIPTION: Pop this walk's object stack. Objects on the stack are NOT
    318 *              deleted by this routine.
    319 *
    320 ******************************************************************************/
    321
    322acpi_status
    323acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state *walk_state)
    324{
    325	u32 i;
    326
    327	ACPI_FUNCTION_NAME(ds_obj_stack_pop);
    328
    329	for (i = 0; i < pop_count; i++) {
    330
    331		/* Check for stack underflow */
    332
    333		if (walk_state->num_operands == 0) {
    334			ACPI_ERROR((AE_INFO,
    335				    "Object stack underflow! Count=%X State=%p #Ops=%u",
    336				    pop_count, walk_state,
    337				    walk_state->num_operands));
    338			return (AE_STACK_UNDERFLOW);
    339		}
    340
    341		/* Just set the stack entry to null */
    342
    343		walk_state->num_operands--;
    344		walk_state->operands[walk_state->num_operands] = NULL;
    345	}
    346
    347	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%u\n",
    348			  pop_count, walk_state, walk_state->num_operands));
    349
    350	return (AE_OK);
    351}
    352
    353/*******************************************************************************
    354 *
    355 * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
    356 *
    357 * PARAMETERS:  pop_count           - Number of objects/entries to pop
    358 *              walk_state          - Current Walk state
    359 *
    360 * RETURN:      Status
    361 *
    362 * DESCRIPTION: Pop this walk's object stack and delete each object that is
    363 *              popped off.
    364 *
    365 ******************************************************************************/
    366
    367void
    368acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
    369				 struct acpi_walk_state *walk_state)
    370{
    371	s32 i;
    372	union acpi_operand_object *obj_desc;
    373
    374	ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);
    375
    376	if (pop_count == 0) {
    377		return;
    378	}
    379
    380	for (i = (s32)pop_count - 1; i >= 0; i--) {
    381		if (walk_state->num_operands == 0) {
    382			return;
    383		}
    384
    385		/* Pop the stack and delete an object if present in this stack entry */
    386
    387		walk_state->num_operands--;
    388		obj_desc = walk_state->operands[i];
    389		if (obj_desc) {
    390			acpi_ut_remove_reference(walk_state->operands[i]);
    391			walk_state->operands[i] = NULL;
    392		}
    393	}
    394
    395	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
    396			  pop_count, walk_state, walk_state->num_operands));
    397}
    398
    399/*******************************************************************************
    400 *
    401 * FUNCTION:    acpi_ds_get_current_walk_state
    402 *
    403 * PARAMETERS:  thread          - Get current active state for this Thread
    404 *
    405 * RETURN:      Pointer to the current walk state
    406 *
    407 * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
    408 *              walk state.)
    409 *
    410 ******************************************************************************/
    411
    412struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
    413						       *thread)
    414{
    415	ACPI_FUNCTION_NAME(ds_get_current_walk_state);
    416
    417	if (!thread) {
    418		return (NULL);
    419	}
    420
    421	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
    422			  thread->walk_state_list));
    423
    424	return (thread->walk_state_list);
    425}
    426
    427/*******************************************************************************
    428 *
    429 * FUNCTION:    acpi_ds_push_walk_state
    430 *
    431 * PARAMETERS:  walk_state      - State to push
    432 *              thread          - Thread state object
    433 *
    434 * RETURN:      None
    435 *
    436 * DESCRIPTION: Place the Thread state at the head of the state list
    437 *
    438 ******************************************************************************/
    439
    440void
    441acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
    442			struct acpi_thread_state *thread)
    443{
    444	ACPI_FUNCTION_TRACE(ds_push_walk_state);
    445
    446	walk_state->next = thread->walk_state_list;
    447	thread->walk_state_list = walk_state;
    448
    449	return_VOID;
    450}
    451
    452/*******************************************************************************
    453 *
    454 * FUNCTION:    acpi_ds_pop_walk_state
    455 *
    456 * PARAMETERS:  thread      - Current thread state
    457 *
    458 * RETURN:      A walk_state object popped from the thread's stack
    459 *
    460 * DESCRIPTION: Remove and return the walkstate object that is at the head of
    461 *              the walk stack for the given walk list. NULL indicates that
    462 *              the list is empty.
    463 *
    464 ******************************************************************************/
    465
    466struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
    467{
    468	struct acpi_walk_state *walk_state;
    469
    470	ACPI_FUNCTION_TRACE(ds_pop_walk_state);
    471
    472	walk_state = thread->walk_state_list;
    473
    474	if (walk_state) {
    475
    476		/* Next walk state becomes the current walk state */
    477
    478		thread->walk_state_list = walk_state->next;
    479
    480		/*
    481		 * Don't clear the NEXT field, this serves as an indicator
    482		 * that there is a parent WALK STATE
    483		 * Do Not: walk_state->Next = NULL;
    484		 */
    485	}
    486
    487	return_PTR(walk_state);
    488}
    489
    490/*******************************************************************************
    491 *
    492 * FUNCTION:    acpi_ds_create_walk_state
    493 *
    494 * PARAMETERS:  owner_id        - ID for object creation
    495 *              origin          - Starting point for this walk
    496 *              method_desc     - Method object
    497 *              thread          - Current thread state
    498 *
    499 * RETURN:      Pointer to the new walk state.
    500 *
    501 * DESCRIPTION: Allocate and initialize a new walk state. The current walk
    502 *              state is set to this new state.
    503 *
    504 ******************************************************************************/
    505
    506struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id,
    507						  union acpi_parse_object
    508						  *origin,
    509						  union acpi_operand_object
    510						  *method_desc,
    511						  struct acpi_thread_state
    512						  *thread)
    513{
    514	struct acpi_walk_state *walk_state;
    515
    516	ACPI_FUNCTION_TRACE(ds_create_walk_state);
    517
    518	walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
    519	if (!walk_state) {
    520		return_PTR(NULL);
    521	}
    522
    523	walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
    524	walk_state->method_desc = method_desc;
    525	walk_state->owner_id = owner_id;
    526	walk_state->origin = origin;
    527	walk_state->thread = thread;
    528
    529	walk_state->parser_state.start_op = origin;
    530
    531	/* Init the method args/local */
    532
    533#ifndef ACPI_CONSTANT_EVAL_ONLY
    534	acpi_ds_method_data_init(walk_state);
    535#endif
    536
    537	/* Put the new state at the head of the walk list */
    538
    539	if (thread) {
    540		acpi_ds_push_walk_state(walk_state, thread);
    541	}
    542
    543	return_PTR(walk_state);
    544}
    545
    546/*******************************************************************************
    547 *
    548 * FUNCTION:    acpi_ds_init_aml_walk
    549 *
    550 * PARAMETERS:  walk_state      - New state to be initialized
    551 *              op              - Current parse op
    552 *              method_node     - Control method NS node, if any
    553 *              aml_start       - Start of AML
    554 *              aml_length      - Length of AML
    555 *              info            - Method info block (params, etc.)
    556 *              pass_number     - 1, 2, or 3
    557 *
    558 * RETURN:      Status
    559 *
    560 * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
    561 *
    562 ******************************************************************************/
    563
    564acpi_status
    565acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
    566		      union acpi_parse_object *op,
    567		      struct acpi_namespace_node *method_node,
    568		      u8 * aml_start,
    569		      u32 aml_length,
    570		      struct acpi_evaluate_info *info, u8 pass_number)
    571{
    572	acpi_status status;
    573	struct acpi_parse_state *parser_state = &walk_state->parser_state;
    574	union acpi_parse_object *extra_op;
    575
    576	ACPI_FUNCTION_TRACE(ds_init_aml_walk);
    577
    578	walk_state->parser_state.aml =
    579	    walk_state->parser_state.aml_start = aml_start;
    580	walk_state->parser_state.aml_end =
    581	    walk_state->parser_state.pkg_end = aml_start + aml_length;
    582
    583	/* The next_op of the next_walk will be the beginning of the method */
    584
    585	walk_state->next_op = NULL;
    586	walk_state->pass_number = pass_number;
    587
    588	if (info) {
    589		walk_state->params = info->parameters;
    590		walk_state->caller_return_desc = &info->return_object;
    591	}
    592
    593	status = acpi_ps_init_scope(&walk_state->parser_state, op);
    594	if (ACPI_FAILURE(status)) {
    595		return_ACPI_STATUS(status);
    596	}
    597
    598	if (method_node) {
    599		walk_state->parser_state.start_node = method_node;
    600		walk_state->walk_type = ACPI_WALK_METHOD;
    601		walk_state->method_node = method_node;
    602		walk_state->method_desc =
    603		    acpi_ns_get_attached_object(method_node);
    604
    605		/* Push start scope on scope stack and make it current  */
    606
    607		status =
    608		    acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
    609					     walk_state);
    610		if (ACPI_FAILURE(status)) {
    611			return_ACPI_STATUS(status);
    612		}
    613
    614		/* Init the method arguments */
    615
    616		status = acpi_ds_method_data_init_args(walk_state->params,
    617						       ACPI_METHOD_NUM_ARGS,
    618						       walk_state);
    619		if (ACPI_FAILURE(status)) {
    620			return_ACPI_STATUS(status);
    621		}
    622	} else {
    623		/*
    624		 * Setup the current scope.
    625		 * Find a Named Op that has a namespace node associated with it.
    626		 * search upwards from this Op. Current scope is the first
    627		 * Op with a namespace node.
    628		 */
    629		extra_op = parser_state->start_op;
    630		while (extra_op && !extra_op->common.node) {
    631			extra_op = extra_op->common.parent;
    632		}
    633
    634		if (!extra_op) {
    635			parser_state->start_node = NULL;
    636		} else {
    637			parser_state->start_node = extra_op->common.node;
    638		}
    639
    640		if (parser_state->start_node) {
    641
    642			/* Push start scope on scope stack and make it current  */
    643
    644			status =
    645			    acpi_ds_scope_stack_push(parser_state->start_node,
    646						     parser_state->start_node->
    647						     type, walk_state);
    648			if (ACPI_FAILURE(status)) {
    649				return_ACPI_STATUS(status);
    650			}
    651		}
    652	}
    653
    654	status = acpi_ds_init_callbacks(walk_state, pass_number);
    655	return_ACPI_STATUS(status);
    656}
    657
    658/*******************************************************************************
    659 *
    660 * FUNCTION:    acpi_ds_delete_walk_state
    661 *
    662 * PARAMETERS:  walk_state      - State to delete
    663 *
    664 * RETURN:      Status
    665 *
    666 * DESCRIPTION: Delete a walk state including all internal data structures
    667 *
    668 ******************************************************************************/
    669
    670void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
    671{
    672	union acpi_generic_state *state;
    673
    674	ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);
    675
    676	if (!walk_state) {
    677		return_VOID;
    678	}
    679
    680	if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
    681		ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
    682			    walk_state));
    683		return_VOID;
    684	}
    685
    686	/* There should not be any open scopes */
    687
    688	if (walk_state->parser_state.scope) {
    689		ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
    690			    walk_state));
    691		acpi_ps_cleanup_scope(&walk_state->parser_state);
    692	}
    693
    694	/* Always must free any linked control states */
    695
    696	while (walk_state->control_state) {
    697		state = walk_state->control_state;
    698		walk_state->control_state = state->common.next;
    699
    700		acpi_ut_delete_generic_state(state);
    701	}
    702
    703	/* Always must free any linked parse states */
    704
    705	while (walk_state->scope_info) {
    706		state = walk_state->scope_info;
    707		walk_state->scope_info = state->common.next;
    708
    709		acpi_ut_delete_generic_state(state);
    710	}
    711
    712	/* Always must free any stacked result states */
    713
    714	while (walk_state->results) {
    715		state = walk_state->results;
    716		walk_state->results = state->common.next;
    717
    718		acpi_ut_delete_generic_state(state);
    719	}
    720
    721	ACPI_FREE(walk_state);
    722	return_VOID;
    723}