IV61040: JAVACORE DEADLOCK WITH JNI DETACHCURRENTTHREAD()

APAR status

• Closed as program error.

Error description

• Error Message: N/A
  .
  Stack Trace: Thread writing javacore:libpthreads.a
  ._global_lock_common + 0464libpthreads.a  ._mutex_lock +
  02F0libj9thr24.so  .j9thread_get_state@AF13_8 +
  0028libj9dmp24.so  .getVMThreadStateHelper + 00BClibj9dmp24.so
  .getVMThreadRawState + 0030libj9dmp24.so
  .protectedGetVMThreadRawState + 0028libj9prt24.so
  .j9sig_protect + 013Clibj9dmp24.so
  .writeMonitorObject__18JavaCoreDumpWriterFP15J9ThreadMonitorP8J9
  Object + 0354libj9dmp24.so
  .writeMonitorSection__18JavaCoreDumpWriterFv + 00D0libj9dmp24.so
   .protectedWriteSection + 0018libj9prt24.so  .j9sig_protect +
  013Clibj9dmp24.so
  .__ct__18JavaCoreDumpWriterFPCcP16J9RASdumpContextP14J9RASdumpAg
  ent + 0374libj9dmp24.so  .runJavadump + 0020libj9dmp24.so
  .doJavaDump + 0048libj9dmp24.so  .protectedDumpFunction +
  0024libj9prt24.so  .j9sig_protect + 013Clibj9dmp24.so
  .runDumpFunction + 0064libj9dmp24.so  .runDumpAgent +
  032Clibj9dmp24.so  .triggerDumpAgents + 02E8libjclscar_24.so
  .sigQuitHandler + 00D4libj9prt24.so  .j9sig_protect +
  013Clibjclscar_24.so  .sigQuitWrapper + 0038libj9prt24.so
  .asynchSignalReporter + 0198libj9thr24.so  .thread_wrapper +
  0130Thread running JNI DetachCurrentThread():libpthreads.a
  ._global_lock_common + 0464libpthreads.a  ._mutex_lock +
  02F0libj9thr24.so  .threadFree + 002Clibj9thr24.so
  .threadDestroy + 0080libj9thr24.so  .j9thread_detach +
  00B8libj9vm24.so  .DetachCurrentThread + 007C
  .
  Javacore triggered via kill -3 was seen to hang, with the
  javacore file truncated in the LOCKS section
  

Local fix

Problem summary

• The problem is caused when the VM is collecting thread
  information for the javacore dump at the same time as the VM
  data structures for a thread are in the process of being deleted
  via a JNI DetachCurrentThread() call.
  

Problem conclusion

• This APAR will be fixed in the following Java Releases:
     6    SR16 FP1    (6.0.16.1)
  .
  The VM has been updated to avoid accessing the data for threads
  that are in the process of being detached.
  

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

  J9 COMMON CODE

• Fixed component ID

  620700127

Applicable component levels

• R600 PSY

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