--- old/src/hotspot/cpu/s390/gc/g1/g1BarrierSetAssembler_s390.cpp	2018-06-13 04:30:23.601642997 -0400
+++ new/src/hotspot/cpu/s390/gc/g1/g1BarrierSetAssembler_s390.cpp	2018-06-13 04:30:23.289626612 -0400
@@ -403,7 +403,7 @@
   __ z_tmll(tmp1, JNIHandles::weak_tag_mask); // Test for jweak tag.
   __ z_braz(Lnot_weak);
   __ verify_oop(value);
-  DecoratorSet decorators = IN_ROOT | ON_PHANTOM_OOP_REF;
+  DecoratorSet decorators = IN_NATIVE | ON_PHANTOM_OOP_REF;
   g1_write_barrier_pre(masm, decorators, (const Address*)NULL, value, noreg, tmp1, tmp2, true);
   __ bind(Lnot_weak);
   __ verify_oop(value);