--- old/src/hotspot/share/runtime/biasedLocking.cpp	2019-05-03 10:53:55.847395663 +0200
+++ new/src/hotspot/share/runtime/biasedLocking.cpp	2019-05-03 10:53:55.381379821 +0200
@@ -627,7 +627,7 @@
   // update the heuristics because doing so may cause unwanted bulk
   // revocations (which are expensive) to occur.
   markOop mark = obj->mark();
-  if (mark->is_biased_anonymously()) {
+  if (mark->is_biased_anonymously() && !attempt_rebias) {
     // We are probably trying to revoke the bias of this object due to
     // an identity hash code computation. Try to revoke the bias
     // without a safepoint. This is possible if we can successfully
@@ -729,7 +729,8 @@
     markOop mark = obj->mark();
     Klass *k = obj->klass();
     markOop prototype_header = k->prototype_header();
-    if (mark->biased_locker_is((JavaThread*) THREAD) &&
+    if (mark->has_bias_pattern() &&
+        mark->biased_locker() == ((JavaThread*) THREAD) &&
         prototype_header->bias_epoch() == mark->bias_epoch()) {
       // A thread is trying to revoke the bias of an object biased
       // toward it, again likely due to an identity hash code