JDK-6861660 : OopMapBlock count/size confusion
  • Type: Bug
  • Component: hotspot
  • Sub-Component: runtime
  • Affected Version: hs11
  • Priority: P3
  • Status: Closed
  • Resolution: Fixed
  • OS: generic
  • CPU: generic
  • Submitted: 2009-07-17
  • Updated: 2010-04-28
  • Resolved: 2010-04-28
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JDK 6 JDK 7 Other
6u18Fixed 7Fixed hs16Fixed
Related Reports
Relates :  
Code in instanceKlass, classFileParser and elsewhere assumes that sizeof(OopMapBlock) <= sizeof(HeapWord), and thus confuses the count of oop map blocks with their size in words in several places.  If OopMapBlock is made larger than a HeapWord, the VM crashes quickly.

EVALUATION http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/b37c246bf7ce

EVALUATION http://hg.openjdk.java.net/hsx/hsx16/master/rev/5a53320cd23f

EVALUATION http://hg.openjdk.java.net/hsx/hsx16/baseline/rev/5a53320cd23f

SUGGESTED FIX Patch attached as 6861660.patch.

EVALUATION http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/b37c246bf7ce

EVALUATION See description. Change the code to use counts of OopMapBlocks and to convert to HeapWord sizes when necessary.