--- old/src/hotspot/share/gc/z/zMark.cpp	2019-09-04 13:48:36.091089637 +0200
+++ new/src/hotspot/share/gc/z/zMark.cpp	2019-09-04 13:48:35.771078807 +0200
@@ -133,6 +133,9 @@
     // Update thread local address bad mask
     ZThreadLocalData::set_address_bad_mask(thread, ZAddressBadMask);
 
+    // Mark invisible root
+    ZThreadLocalData::do_invisible_root(thread, ZBarrier::mark_barrier_on_invisible_root_oop_field);
+
     // Retire TLAB
     ZThreadLocalAllocBuffer::retire(thread);
   }
@@ -156,7 +159,7 @@
   ZMarkRootsTask(ZMark* mark) :
       ZTask("ZMarkRootsTask"),
       _mark(mark),
-      _roots(true /* visit_invisible */, false /* visit_jvmti_weak_export */) {}
+      _roots(false /* visit_jvmti_weak_export */) {}
 
   virtual void work() {
     _roots.oops_do(&_cl);
@@ -282,7 +285,7 @@
   follow_array(addr, size, finalizable);
 }
 
-void ZMark::follow_array_object(objArrayOop obj, bool finalizable) {
+void ZMark::follow_array_object(objArrayOop obj, bool follow, bool finalizable) {
   if (finalizable) {
     ZMarkBarrierOopClosure<true /* finalizable */> cl;
     cl.do_klass(obj->klass());
@@ -291,10 +294,11 @@
     cl.do_klass(obj->klass());
   }
 
-  const uintptr_t addr = (uintptr_t)obj->base();
-  const size_t size = (size_t)obj->length() * oopSize;
-
-  follow_array(addr, size, finalizable);
+  if (follow) {
+    const uintptr_t addr = (uintptr_t)obj->base();
+    const size_t size = (size_t)obj->length() * oopSize;
+    follow_array(addr, size, finalizable);
+  }
 }
 
 void ZMark::follow_object(oop obj, bool finalizable) {
@@ -348,7 +352,7 @@
   }
 
   if (is_array(addr)) {
-    follow_array_object(objArrayOop(ZOop::from_address(addr)), finalizable);
+    follow_array_object(objArrayOop(ZOop::from_address(addr)), entry.follow(), finalizable);
   } else {
     follow_object(ZOop::from_address(addr), finalizable);
   }