Immix fails OutOfMemory MMTk harness test

Immix fails trying to access an unmapped page in the harness. The OutOfMemory test creates 0% live data until an out of memory failure occurs.

java -jar target/mmtk/mmtk-harness.jar MMTk/harness/test-scripts/OutOfMemory.script plan=org.mmtk.plan.immix.Immix

Collector 0 caused unexpected exception: java.lang.RuntimeException: Page not mapped: 0x00004000
at org.vmmagic.unboxed.SimulatedMemory.getPage(SimulatedMemory.java:63)
at org.vmmagic.unboxed.SimulatedMemory.getPage(SimulatedMemory.java:57)
at org.vmmagic.unboxed.SimulatedMemory.getInt(SimulatedMemory.java:104)
at org.vmmagic.unboxed.SimulatedMemory.getInt(SimulatedMemory.java:73)
at org.vmmagic.unboxed.Address.loadInt(Address.java:478)
at org.vmmagic.unboxed.Address.loadAddress(Address.java:542)
at org.mmtk.policy.immix.Chunk.getHighWater(Chunk.java:153)
at org.mmtk.policy.immix.ImmixSpace.getUsableLinesInRegion(ImmixSpace.java:666)
at org.mmtk.policy.immix.ImmixSpace.getAvailableLines(ImmixSpace.java:632)
at org.mmtk.policy.immix.Defrag.establishDefragSpillThreshold(Defrag.java:174)
at org.mmtk.policy.immix.Defrag.prepare(Defrag.java:113)
at org.mmtk.policy.immix.ImmixSpace.prepare(ImmixSpace.java:139)
at org.mmtk.plan.immix.Immix.collectionPhase(Immix.java:100)
at org.mmtk.plan.Phase.processPhaseStack(Phase.java:470)
at org.mmtk.plan.Phase.beginNewPhaseStack(Phase.java:390)
at org.mmtk.plan.StopTheWorldCollector.collect(StopTheWorldCollector.java:39)
at org.mmtk.harness.Collector.run(Collector.java:229)