ACPICA: Fix race condition with AcpiWalkNamespace.

Fixed a problem with a possible race condition between threads executing
AcpiWalkNamespace and the AML interpreter. This condition was removed by
modifying AcpiWalkNamespace to (by default) ignore all temporary
namespace entries created during any concurrent control method execution

Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 8 insertions, 4 deletions

diff --git a/include/acpi/aclocal.h b/include/acpi/aclocal.h
index 553763d7312..287da6fe256 100644
--- a/include/acpi/aclocal.h
+++ b/include/acpi/aclocal.h
@@ -204,7 +204,7 @@ struct acpi_namespace_node {
 /* Namespace Node flags */
 
 #define ANOBJ_END_OF_PEER_LIST          0x01    /* End-of-list, Peer field points to parent */
-#define ANOBJ_RESERVED                  0x02    /* Available for future use */
+#define ANOBJ_TEMPORARY                 0x02    /* Node is create by a method and is temporary */
 #define ANOBJ_METHOD_ARG                0x04    /* Node is a method argument */
 #define ANOBJ_METHOD_LOCAL              0x08    /* Node is a method local */
 #define ANOBJ_SUBTREE_HAS_INI           0x10    /* Used to optimize device initialization */
diff --git a/include/acpi/acnamesp.h b/include/acpi/acnamesp.h
index b3b9f0ec79c..19a61292af6 100644
--- a/include/acpi/acnamesp.h
+++ b/include/acpi/acnamesp.h
@@ -65,9 +65,13 @@
 #define ACPI_NS_ERROR_IF_FOUND      0x08
 #define ACPI_NS_PREFIX_IS_SCOPE     0x10
 #define ACPI_NS_EXTERNAL            0x20
+#define ACPI_NS_TEMPORARY           0x40
 
-#define ACPI_NS_WALK_UNLOCK         TRUE
-#define ACPI_NS_WALK_NO_UNLOCK      FALSE
+/* Flags for acpi_ns_walk_namespace */
+
+#define ACPI_NS_WALK_NO_UNLOCK      0
+#define ACPI_NS_WALK_UNLOCK         0x01
+#define ACPI_NS_WALK_TEMP_NODES     0x02
 
 /*
  * nsinit - Namespace initialization
@@ -92,7 +96,7 @@ acpi_status
 acpi_ns_walk_namespace(acpi_object_type type,
                        acpi_handle start_object,
                        u32 max_depth,
-                       u8 unlock_before_callback,
+                       u32 flags,
                        acpi_walk_callback user_function,
                        void *context, void **return_value);