Signed-off-by: Zhou Peng <zhoupeng@xxxxxxxxxxxxxxx>

--- a/tools/libxl/libxl_dm.c    Wed Apr 13 14:08:41 2011 +0800
+++ b/tools/libxl/libxl_dm.c    Wed Apr 13 14:20:37 2011 +0800
@@ -197,7 +197,7 @@ static char ** libxl_build_device_model_
         int display = 0;
         const char *listen = "127.0.0.1";
 
-        if (info->vncpasswd && info->vncpasswd[0]) {
+        if (info->vncpasswd && !info->vncpasswd[0]) {
             assert(!"missing code for supplying vnc password to qemu");
         }
         flexarray_append(dm_args, "-vnc");