IT26421: amqzlaa0 process terminates due to an access violation (SIGSEGV)

APAR status

• Closed as program error.

Error description

• Failure data capture (FDC) records are generated showing that an
  agent process (amqzlaa0)
  terminates with an access violation/SIGSEGV.
  The following can be seen in an FDC:
  
  Operating System  :- Windows Ver 6.2 (7) Server Standard x64
  Edition,
  LVLS              :- 8.0.0.3
  Product Long Name :- WebSphere MQ for Windows (x64 platform)
  Probe Id          :- XC130031
  Component         :- xehExceptionHandler
  Process Name      :- D:\Program Files\IBM\WebSphere
  MQ\bin64\amqzlaa0.exe
  Major Errorcode   :- xecF_E_UNEXPECTED_SYSTEM_RC
  Minor Errorcode   :- OK
  Probe Type        :- MSGAMQ6119
  Probe Description :- AMQ6109: An internal WebSphere MQ error
  has occurred.
  
  FDCSequenceNumber :- 0
  Comment1          :- Access Violation at address
  00000053E7FCEC44 when reading
  MQM Trace History
  Data: 0x10806020
  Data: 0x00000001 0x00000000
  --} xlsWaitEvent rc=xecL_W_TIMEOUT
  -} zcpReceiveOnPipe rc=zrcC_E_TIMEOUT
  -{ zlaPerformHealthCheck
  --{ xcsCheckHandle
  --} xcsCheckHandle rc=xecP_E_INVALID_PID
  -} zlaPerformHealthCheck rc=xecP_E_INVALID_PID
  -{ zcpReceiveOnPipe
  --{ xlsWaitEvent
  --} xlsWaitEvent rc=xecL_W_TIMEOUT
  -} zcpReceiveOnPipe rc=zrcC_E_TIMEOUT
  -{ zlaPerformHealthCheck
  --{ xcsCheckHandle
  --} xcsCheckHandle rc=xecP_E_INVALID_PID
  -} zlaPerformHealthCheck rc=xecP_E_INVALID_PID
   ...
  ---{ xcsFreeMemFn
  ---} xcsFreeMemFn rc=OK
  ---{ xcsReleaseThreadMutexSem
  ---} xcsReleaseThreadMutexSem rc=OK
  --} xcsDisconnectSharedMemSet rc=OK
  --{ xcsFreeQuickCell
  --} xcsFreeQuickCell rc=OK
  --{ xllDropSubpoolHandles
  --} xllDropSubpoolHandles rc=OK
  -} xcsDisconnectSharedSubpool rc=OK
  -{ xcsReleaseThreadMutexSem
  -} xcsReleaseThreadMutexSem rc=OK
  } xcsTerminate rc=OK
  { xcsFFST
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This may be seen by any user of IBM MQ, although the problem may
  be more prevalent on busy systems.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A race condition caused IBM MQ to try to reference a memory
  block that was recently detached by another thread and this
  caused a segmentation violation.
  

Problem conclusion

• The IBM MQ code has been reordered so that the memory block is
  not detached while other threads may still be using it.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.4
  
  
  
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

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

  IBM MQ BASE MP

• Fixed component ID

  5724H7251

Applicable component levels