ACPICA: Debugger: Lock namespace for duration of a namespace dump

Prevents issues if the namespace is changing underneath the
debugger.  Especially temporary nodes, since the debugger displays
these also.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Reviewed-by: Rafael Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/acpica/nsdump.c b/drivers/acpi/acpica/nsdump.c
index a54dc39e304b2e2a0c34835aca4464b17032d251..82693c3eb25797dfda7139335c29c70a42771822 100644 (file)
--- a/drivers/acpi/acpica/nsdump.c
+++ b/drivers/acpi/acpica/nsdump.c
@@ -624,9 +624,22 @@ acpi_ns_dump_objects(acpi_object_type type,
                     acpi_owner_id owner_id, acpi_handle start_handle)
 {
        struct acpi_walk_info info;
+       acpi_status status;
 
        ACPI_FUNCTION_ENTRY();
 
+       /*
+        * Just lock the entire namespace for the duration of the dump.
+        * We don't want any changes to the namespace during this time,
+        * especially the temporary nodes since we are going to display
+        * them also.
+        */
+       status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+       if (ACPI_FAILURE(status)) {
+               acpi_os_printf("Could not acquire namespace mutex\n");
+               return;
+       }
+
        info.debug_level = ACPI_LV_TABLES;
        info.owner_id = owner_id;
        info.display_type = display_type;
@@ -636,6 +649,8 @@ acpi_ns_dump_objects(acpi_object_type type,
                                     ACPI_NS_WALK_TEMP_NODES,
                                     acpi_ns_dump_one_object, NULL,
                                     (void *)&info, NULL);
+
+       (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 }
 #endif                         /* ACPI_FUTURE_USAGE */