--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Mon Jan 26 15:51:28 2015 -0800
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Tue Jan 19 18:16:40 2016 +0000
@@ -3767,6 +3767,9 @@
             _dcq.enqueue(card_ptr);
           }
         }
+        assert(hrrs.n_yielded() == r->rem_set()->occupied(),
+               err_msg("Remembered set hash maps out of sync, cur: " SIZE_FORMAT " entries, next: " SIZE_FORMAT " entries",
+               hrrs.n_yielded(), r->rem_set()->occupied()));
         r->rem_set()->clear_locked();
       }
       assert(r->rem_set()->is_empty(), "At this point any humongous candidate remembered set must be empty.");
@@ -4089,6 +4092,13 @@
 
         g1_policy()->finalize_cset(target_pause_time_ms, evacuation_info);
 
+        // Make sure the remembered sets are up to date. This needs to be
+        // done before register_humongous_regions_with_cset(), because the
+        // remembered sets are used there to choose eager reclaim candidates.
+        // If the remembered sets are not up to date we might miss some
+        // entries that need to be handled.
+        g1_rem_set()->cleanupHRRS();
+
         register_humongous_regions_with_in_cset_fast_test();
 
         assert(check_cset_fast_test(), "Inconsistency in the InCSetState table.");

--- a/src/share/vm/gc_implementation/g1/g1RemSet.cpp	Mon Jan 26 15:51:28 2015 -0800
+++ b/src/share/vm/gc_implementation/g1/g1RemSet.cpp	Tue Jan 19 18:16:40 2016 +0000
@@ -335,7 +335,6 @@
 }
 
 void G1RemSet::prepare_for_oops_into_collection_set_do() {
-  cleanupHRRS();
   _g1->set_refine_cte_cl_concurrency(false);
   DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
   dcqs.concatenate_logs();

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/gc_implementation/g1/TestNoEagerReclaimOfHumongousRegions.java	Tue Jan 19 18:16:40 2016 +0000
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test TestNoEagerReclaimOfHumongousRegions
+ * @bug 8139424
+ * @summary Test to check that a live humongous object is not eagerly reclaimed. This is a regression test for
+ *          8139424 and the test will crash if an eager reclaim occur. The test is not 100% deterministic and
+ *          might pass even if there are problems in the code, but it will never crash unless there is a problem.
+ * @requires vm.gc=="G1" | vm.gc=="null"
+ * @key gc
+ * @library /testlibrary /testlibrary/whitebox
+ * @modules java.base/sun.misc
+ * @build TestNoEagerReclaimOfHumongousRegions
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ *                              sun.hotspot.WhiteBox$WhiteBoxPermission
+ * @run main/othervm -Xbootclasspath/a:. -XX:+PrintGC -XX:+UseG1GC -XX:MaxTenuringThreshold=0 -XX:G1RSetSparseRegionEntries=32 -XX:G1HeapRegionSize=1m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:+UnlockExperimentalVMOptions -XX:+G1TraceEagerReclaimHumongousObjects TestNoEagerReclaimOfHumongousRegions
+ */
+
+import java.util.LinkedList;
+
+import sun.hotspot.WhiteBox;
+
+public class TestNoEagerReclaimOfHumongousRegions {
+    // Helper class to keep reference to humongous byte[].
+    static class LargeRef {
+        private byte[] _ref;
+
+        LargeRef(byte[] ref) {
+            _ref = ref;
+        }
+
+        byte[] ref() { return _ref; }
+    }
+
+    static LargeRef humongous_reference_holder;
+
+    public static void main(String[] args) throws InterruptedException{
+        WhiteBox wb = WhiteBox.getWhiteBox();
+        LinkedList<Object> garbageAndRefList = new LinkedList<Object>();
+        // Creating a 1M large byte array. Since the test specifies the heap
+        // region size to be 1m this will be a humongous object. We then
+        // store a pointer to the array in the static object to keep it live
+        // during the whole test.
+        humongous_reference_holder = new LargeRef(new byte[1 * 1024 * 1024]);
+
+        // Create some garbage and a reference to the humongous object each round.
+        for (int i = 0; i < 32; i++) {
+            garbageAndRefList.add(new byte[400*1000]);
+            garbageAndRefList.add(new LargeRef(humongous_reference_holder.ref()));
+
+            // Promote to old, goal is to get rem-set entries for the humongous
+            // object from different regions. The test specifies MaxTenuringThreshold=0,
+            // this will make sure we get objects promoted to old at once.
+            wb.youngGC();
+        }
+        // Clear the garbage and reference list.
+        garbageAndRefList.clear();
+
+        // Run a concurrent mark cycle to mark all references but the static one as dead.
+        wb.g1StartConcMarkCycle();
+        while (wb.g1InConcurrentMark()) {
+            Thread.sleep(100);
+        }
+
+        // Run a young collection to make sure humongous object still can't be eagerly reclaimed.
+        wb.youngGC();
+        // Will crash/assert if humongous object has been reclaimed.
+        wb.fullGC();
+    }
+}