--- old/src/hotspot/share/classfile/systemDictionary.cpp	2018-10-21 17:55:03.071145403 -0700
+++ new/src/hotspot/share/classfile/systemDictionary.cpp	2018-10-21 17:55:02.791134641 -0700
@@ -1489,8 +1489,7 @@
            !search_only_bootloader_append,
            "Attempt to load a class outside of boot loader's module path");
 
-    // Search the shared system dictionary for classes preloaded into the
-    // shared spaces.
+    // Search for classes in the CDS archive.
     InstanceKlass* k = NULL;
     {
 #if INCLUDE_CDS
@@ -1958,7 +1957,7 @@
   // Allocate private object used as system class loader lock
   _system_loader_lock_obj = oopFactory::new_intArray(0, CHECK);
   // Initialize basic classes
-  resolve_preloaded_classes(CHECK);
+  resolve_well_known_classes(CHECK);
 }
 
 // Compact table of directions on the initialization of klasses:
@@ -1971,6 +1970,22 @@
   0
 };
 
+#ifdef ASSERT
+bool SystemDictionary::is_well_known_klass(Symbol* class_name) {
+  for (int i = 0; ; i++) {
+    int sid = wk_init_info[i];
+    if (sid == 0) {
+      break;
+    }
+    Symbol* symbol = vmSymbols::symbol_at((vmSymbols::SID)sid);
+    if (class_name == symbol) {
+      return true;
+    }
+  }
+  return false;
+}
+#endif
+
 bool SystemDictionary::resolve_wk_klass(WKID id, TRAPS) {
   assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob");
   int sid = wk_init_info[id - FIRST_WKID];
@@ -2002,8 +2017,8 @@
   start_id = limit_id;
 }
 
-void SystemDictionary::resolve_preloaded_classes(TRAPS) {
-  assert(WK_KLASS(Object_klass) == NULL, "preloaded classes should only be initialized once");
+void SystemDictionary::resolve_well_known_classes(TRAPS) {
+  assert(WK_KLASS(Object_klass) == NULL, "well-known classes should only be initialized once");
 
   // Create the ModuleEntry for java.base.  This call needs to be done here,
   // after vmSymbols::initialize() is called but before any classes are pre-loaded.
@@ -2071,7 +2086,8 @@
   WKID jsr292_group_end   = WK_KLASS_ENUM_NAME(VolatileCallSite_klass);
   resolve_wk_klasses_until(jsr292_group_start, scan, CHECK);
   resolve_wk_klasses_through(jsr292_group_end, scan, CHECK);
-  resolve_wk_klasses_until(NOT_JVMCI(WKID_LIMIT) JVMCI_ONLY(FIRST_JVMCI_WKID), scan, CHECK);
+  WKID last = NOT_JVMCI(WKID_LIMIT) JVMCI_ONLY(FIRST_JVMCI_WKID);
+  resolve_wk_klasses_until(last, scan, CHECK);
 
   _box_klasses[T_BOOLEAN] = WK_KLASS(Boolean_klass);
   _box_klasses[T_CHAR]    = WK_KLASS(Character_klass);
@@ -2088,6 +2104,15 @@
     Method* method = InstanceKlass::cast(ClassLoader_klass())->find_method(vmSymbols::checkPackageAccess_name(), vmSymbols::class_protectiondomain_signature());
     _has_checkPackageAccess = (method != NULL);
   }
+
+  if (UseSharedSpaces) {
+    assert(JvmtiEnvBase::get_phase() <= JVMTI_PHASE_PRIMORDIAL,
+           "All well known classes must be resolved in JVMTI_PHASE_PRIMORDIAL or before");
+    for (int i=FIRST_WKID; i<last; i++) {
+      InstanceKlass* k = _well_known_klasses[i];
+      assert(k->is_shared(), "must not be replaced by JVMTI class file load hook");
+    }
+  }
 }
 
 // Tells if a given klass is a box (wrapper class, such as java.lang.Integer).