From: Bob Moore <robert.moore@xxxxxxxxx>
Fixed a problem with the Alias operator when the target of the
alias is a named ASL operator that opens a new scope -- Scope,
Device, PowerResource, Processor, and ThermalZone. In these cases,
any children of the original operator could not be accessed via
the alias, potentially causing unexpected AE_NOT_FOUND exceptions.
Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@xxxxxxx>
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
---
drivers/acpi/executer/excreate.c | 20 ++++++--
drivers/acpi/namespace/nsaccess.c | 96 +++++++++++++++++++++++--------------
2 files changed, 75 insertions(+), 41 deletions(-)
diff --git a/drivers/acpi/executer/excreate.c b/drivers/acpi/executer/excreate.c
index 6e9a23e..b391439 100644
--- a/drivers/acpi/executer/excreate.c
+++ b/drivers/acpi/executer/excreate.c
@@ -96,6 +96,9 @@ acpi_status acpi_ex_create_alias(struct acpi_walk_state *walk_state)
* to the original Node.
*/
switch (target_node->type) {
+
+ /* For these types, the sub-object can change dynamically via a Store */
+
case ACPI_TYPE_INTEGER:
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
@@ -103,9 +106,18 @@ acpi_status acpi_ex_create_alias(struct acpi_walk_state *walk_state)
case ACPI_TYPE_BUFFER_FIELD:
/*
+ * These types open a new scope, so we need the NS node in order to access
+ * any children.
+ */
+ case ACPI_TYPE_DEVICE:
+ case ACPI_TYPE_POWER:
+ case ACPI_TYPE_PROCESSOR:
+ case ACPI_TYPE_THERMAL:
+ case ACPI_TYPE_LOCAL_SCOPE:
+
+ /*
* The new alias has the type ALIAS and points to the original
- * NS node, not the object itself. This is because for these
- * types, the object can change dynamically via a Store.
+ * NS node, not the object itself.
*/
alias_node->type = ACPI_TYPE_LOCAL_ALIAS;
alias_node->object =
@@ -115,9 +127,7 @@ acpi_status acpi_ex_create_alias(struct acpi_walk_state *walk_state)
case ACPI_TYPE_METHOD:
/*
- * The new alias has the type ALIAS and points to the original
- * NS node, not the object itself. This is because for these
- * types, the object can change dynamically via a Store.
+ * Control method aliases need to be differentiated
*/
alias_node->type = ACPI_TYPE_LOCAL_METHOD_ALIAS;
alias_node->object =
diff --git a/drivers/acpi/namespace/nsaccess.c b/drivers/acpi/namespace/nsaccess.c
index 32a0167..54852fb 100644
--- a/drivers/acpi/namespace/nsaccess.c
+++ b/drivers/acpi/namespace/nsaccess.c
@@ -581,44 +581,68 @@ acpi_ns_lookup(union acpi_generic_state *scope_info,
return_ACPI_STATUS(status);
}
- /*
- * Sanity typecheck of the target object:
- *
- * If 1) This is the last segment (num_segments == 0)
- * 2) And we are looking for a specific type
- * (Not checking for TYPE_ANY)
- * 3) Which is not an alias
- * 4) Which is not a local type (TYPE_SCOPE)
- * 5) And the type of target object is known (not TYPE_ANY)
- * 6) And target object does not match what we are looking for
- *
- * Then we have a type mismatch. Just warn and ignore it.
- */
- if ((num_segments == 0) &&
- (type_to_check_for != ACPI_TYPE_ANY) &&
- (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
- (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
- (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) &&
- (this_node->type != ACPI_TYPE_ANY) &&
- (this_node->type != type_to_check_for)) {
-
- /* Complain about a type mismatch */
-
- ACPI_WARNING((AE_INFO,
- "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
- ACPI_CAST_PTR(char, &simple_name),
- acpi_ut_get_type_name(this_node->type),
- acpi_ut_get_type_name
- (type_to_check_for)));
+ /* More segments to follow? */
+
+ if (num_segments > 0) {
+ /*
+ * If we have an alias to an object that opens a scope (such as a
+ * device or processor), we need to dereference the alias here so that
+ * we can access any children of the original node (via the remaining
+ * segments).
+ */
+ if (this_node->type == ACPI_TYPE_LOCAL_ALIAS) {
+ if (acpi_ns_opens_scope
+ (((struct acpi_namespace_node *)this_node->
+ object)->type)) {
+ this_node =
+ (struct acpi_namespace_node *)
+ this_node->object;
+ }
+ }
}
- /*
- * If this is the last name segment and we are not looking for a
- * specific type, but the type of found object is known, use that type
- * to see if it opens a scope.
- */
- if ((num_segments == 0) && (type == ACPI_TYPE_ANY)) {
- type = this_node->type;
+ /* Special handling for the last segment (num_segments == 0) */
+
+ else {
+ /*
+ * Sanity typecheck of the target object:
+ *
+ * If 1) This is the last segment (num_segments == 0)
+ * 2) And we are looking for a specific type
+ * (Not checking for TYPE_ANY)
+ * 3) Which is not an alias
+ * 4) Which is not a local type (TYPE_SCOPE)
+ * 5) And the type of target object is known (not TYPE_ANY)
+ * 6) And target object does not match what we are looking for
+ *
+ * Then we have a type mismatch. Just warn and ignore it.
+ */
+ if ((type_to_check_for != ACPI_TYPE_ANY) &&
+ (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
+ (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS)
+ && (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE)
+ && (this_node->type != ACPI_TYPE_ANY)
+ && (this_node->type != type_to_check_for)) {
+
+ /* Complain about a type mismatch */
+
+ ACPI_WARNING((AE_INFO,
+ "NsLookup: Type mismatch on %4.4s (%s), searching for (%s)",
+ ACPI_CAST_PTR(char, &simple_name),
+ acpi_ut_get_type_name(this_node->
+ type),
+ acpi_ut_get_type_name
+ (type_to_check_for)));
+ }
+
+ /*
+ * If this is the last name segment and we are not looking for a
+ * specific type, but the type of found object is known, use that type
+ * to (later) see if it opens a scope.
+ */
+ if (type == ACPI_TYPE_ANY) {
+ type = this_node->type;
+ }
}
/* Point to next name segment and make this node current */
--
1.5.5.29.g7134
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