ACPICA: Report error if method creates 2 objects with the same name

Fixed a regression where an error was no
longer emitted if a control method attempts to create 2
objects of the same name. This previously and now returns
AE_ALREADY_EXISTS. When this exception occurs, it invokes
the mechanism that will dynamically serialize the control
method to possible prevent future errors. (BZ 440)

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

diff --git a/drivers/acpi/dispatcher/dswload.c b/drivers/acpi/dispatcher/dswload.c
index d60d062..565d455 100644 (file)
--- a/drivers/acpi/dispatcher/dswload.c
+++ b/drivers/acpi/dispatcher/dswload.c
@@ -547,6 +547,7 @@ acpi_ds_load2_begin_op(struct acpi_walk_state *walk_state,
        acpi_status status;
        acpi_object_type object_type;
        char *buffer_ptr;
+       u32 flags;
 
        ACPI_FUNCTION_TRACE(ds_load2_begin_op);
 
@@ -752,12 +753,20 @@ acpi_ds_load2_begin_op(struct acpi_walk_state *walk_state,
                        break;
                }
 
-               /* Add new entry into namespace */
+               flags = ACPI_NS_NO_UPSEARCH;
+               if (walk_state->pass_number == 3) {
+
+                       /* Execution mode, node cannot already exist */
+
+                       flags |= ACPI_NS_ERROR_IF_FOUND;
+               }
+
+               /* Add new entry or lookup existing entry */
 
                status =
                    acpi_ns_lookup(walk_state->scope_info, buffer_ptr,
-                                  object_type, ACPI_IMODE_LOAD_PASS2,
-                                  ACPI_NS_NO_UPSEARCH, walk_state, &(node));
+                                  object_type, ACPI_IMODE_LOAD_PASS2, flags,
+                                  walk_state, &node);
                break;
        }
 

diff --git a/drivers/acpi/parser/psparse.c b/drivers/acpi/parser/psparse.c
index a02aa62..6e875ce 100644 (file)
--- a/drivers/acpi/parser/psparse.c
+++ b/drivers/acpi/parser/psparse.c
@@ -540,6 +540,11 @@ acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
 
                        if ((status == AE_ALREADY_EXISTS) &&
                            (!walk_state->method_desc->method.mutex)) {
+                               ACPI_INFO((AE_INFO,
+                                          "Marking method %4.4s as Serialized",
+                                          walk_state->method_node->name.
+                                          ascii));
+
                                /*
                                 * Method tried to create an object twice. The probable cause is
                                 * that the method cannot handle reentrancy.