IBM Support

IT16997: SIGSEGV in zsqATOpenBefore accessing address 0+0x4 when queue manager is quiescing

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • The queue manager was quiesced.
    Application activity trace was being used.
    At that moment, the application called MQOPEN with the
    MQOO_FAIL_IF_QUIESCING flag.
    While the queue manager was processing this call, a memory
    exception was generated in the agent process (amqzlaa0) serving
    the application.  FDC files were written from that process, and
    the MQOPEN activity failed.
    ----------------------------------------------------------------
    Probe: XC130003
    Last function executing: zsqATOpenBefore
    
    This FDC might be seen from amqzlaa0 processes, or fastpath
    applications, or fastpath channel programs.
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Users running MQ 8.0.0.2 or higher, who are using application
    activity trace, and are ending their queue manager via quiesce
    option (-w, or -c, or no option).
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    An application called MQOPEN with the option
    MQOO_FAIL_IF_QUIESCING.  While the queue manager was quiescing,
    this caused a path of execution that incorrectly tried to access
    memory via a null pointer.  This caused a memory exception, and
    the MQOPEN activity failed.  An FDC record was also written to
    record the memory exception.
    

Problem conclusion

  • The MQ product code has been corrected to ensure that a null
    pointer is not used in this scenario.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v8.0       8.0.0.6
    v9.0 CD    9.0.1
    v9.0 LTS   9.0.0.1
    
    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

    IT16997

  • Reported component name

    WMQ BASE MULTIP

  • Reported component ID

    5724H7251

  • Reported release

    800

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-09-12

  • Closed date

    2016-09-29

  • Last modified date

    2017-06-01

  • 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

    WMQ BASE MULTIP

  • Fixed component ID

    5724H7251

Applicable component levels

  • R800 PSY

       UP

[{"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:
01 June 2017