src/hotspot/share/classfile/classLoader.cpp

@@ -1639,11 +1639,11 @@
   ModuleEntryTable* null_cld_modules = null_cld->modules();
   if (null_cld_modules == NULL) {
     vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
   }
 
-  {
+  if (ModuleEntryTable::javabase_moduleEntry() == NULL) { // may have been inited by CDS.
     MutexLocker ml(THREAD, Module_lock);
     ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
                                false, vmSymbols::java_base(), NULL, NULL, null_cld);
     if (jb_module == NULL) {
       vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);