IJ15793: CRASH DURING JIT COMPILATION

APAR status

• Closed as program error.

Error description

• Error Message: The JVM stops unexpectedly and, depending on
  configuration, writes crash data including javacore and system
  core. The javacore will indicate that there was a GPF from
  libj9jit29.so with InaccessibleAddress: 0000000000000000. In the
  THREADS section of the javacore the current thread will be one
  of the JIT Compilation threads.
  .
  Stack Trace: This problem can present in different ways
  depending on the platform. In two cases the crash occurred while
  the compiler was generating intermediate code for an
  invokeinterface bytecode instruction:
  TR_J9ByteCodeIlGenerator::numPlaceholderCalls(int)
  TR_J9ByteCodeIlGenerator::genNodeAndPopChildren(<OSB>..<CSB>)
  TR_J9ByteCodeIlGenerator::genInstanceof(int)
  TR_J9ByteCodeIlGenerator::genInvokeInterface(int)
  TR_J9ByteCodeIlGenerator::walker(TR::Block*)
  TR_J9ByteCodeIlGenerator::genILFromByteCodes()
  TR_J9ByteCodeIlGenerator::genIL()
  ---
  TR_J9ByteCodeIlGenerator::genNodeAndPopChildren(<OSB>..<CSB>)
  TR_J9ByteCodeIlGenerator::genInvokeInterface(int)
  TR_J9ByteCodeIlGenerator::genILFromByteCodes()
  TR_J9ByteCodeIlGenerator::internalGenIL()
  TR_J9ByteCodeIlGenerator::genIL()
  In a third case the crash didn't happen until later in
  InvariantArgumentPreexistence:
  TR_InvariantArgumentPreexistence::processNode(<OSB>..<CSB>)
  TR_InvariantArgumentPreexistence::processNode(<OSB>..<CSB>)
  TR_InvariantArgumentPreexistence::perform()
  OMR::Optimizer::performOptimization(<OSB>..<CSB>)
  OMR::Optimizer::optimize()
  OMR::ResolvedMethodSymbol::genIL(<OSB>..<CSB>)
  .
  The problem exists only in Java8 SR5 from FP22 onwards.
  

Local fix

• The method(s) that expose the problem can be excluded from
  compilation by the JIT. For example if the problem shows up in
  two methods packageA.ClassA.method1 and packageB.ClassB.method2
  then an appropriate Xjit option would be:
  -Xjit:exclude={packageA/ClassA.method1(*<PIPE>packageB/ClassB.me
  thod2(*},dontInline={packageA/ClassA.method1(*<PIPE>packageB/Cla
  ssB.method2(*}
  Note that there can be at most one -Xjit option on the command
  line, so if there is already an Xjit option in use it will need
  to be combined with the above for correct operation.
  

Problem summary

• Interface calls that resolve to private methods or methods of
  Object require special handling by the JIT. An error in the code
  for these special cases could lead to dereference of a null
  pointer and the resulting crash. The only bytecode that has been
  observed to cause this crash is an invokeinterface bytecode
  instruction calling getClass().
  

Problem conclusion

• The JIT has been modified to correctly handle the case that
  caused the problem. See the following PR for more detail:
  https://github.com/eclipse/openj9/pull/5500
  .
  This APAR will be fixed in the following Java Releases:
     8    SR5 FP36  (8.0.5.36)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the available
  Service Refreshes and Fix Packs can be found at:
             https://www.ibm.com/developerworks/java/jdk/
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels