IBM Support

IT28499: Memory exception in MQDISC in client application and FDC record with XC130006 xehExceptionHandler

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APAR status

  • Closed as program error.

Error description

  • The application MQDISC call fails.
    
    A failure data capture (FDC) record is generated showing:
    
    Probe Id :- XC130006
    Component :- xehExceptionHandler
    Program Name :- <UsersProgramName>
    UserApp :- TRUE
    Comment1 :- SIGSEGV: address not mapped(0x32)
    
    MQM Function Stack ends with:
    ccigsk_unload
    xcsUnloadFunction
    xcsFFST
    
    Later in the FDC record, the following appears showing a
    LoadedCount of 8, where it should normally be 4.
    
    GSKFn
      :
      LoadedCount       8
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Any user of a multi-threaded MQ C client application that calls
    MQCONN and MQDISC freely on multiple threads concurrently.
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    Library loading code in MQCONN and MQDISC was relying on state
    data in a global variable but this state data was not protected
    by a mutex, where it should have been.
    

Problem conclusion

  • A mutex is now used to protect this state data, and so the
    problem no longer exists.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v8.0       8.0.0.5
    v9.1 CD    9.1.4
    
    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 number

    IT28499

  • Reported component name

    IBM MQ BASE MP

  • Reported component ID

    5724H7251

  • Reported release

    800

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2019-03-18

  • Closed date

    2019-08-19

  • Last modified date

    2019-08-19

  • 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

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"8.0.0.0","Edition":"","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
19 August 2019