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IV69571: FDC WITH PROBEID KN346080 WHEN USING ASYNCHRONOUS CONSUME FUNCTIONALITY

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • When using the asynchronous consume functionality of WebSphere
    MQ, an FDC with probe identifier KN346080 is produced with the
    following call stack:
    
    MQM Function Stack
    zlsMainThread
    zlsProcessMessage
    zlsProcessMQIRequest
    zlsMQGETM
    zsqMQGETM
    kpiMQGETM
    xcsFFST
    
    The FDC may also contain a trace sequence which looks like this:
    
    -----{ kqiWaitForABit
    ------{ xcsWaitEventSem
    -------{ xlsWaitEvent
    Data: 0x00000064 0x80000000
    -------} xlsWaitEvent rc=OK
    ------} xcsWaitEventSem rc=OK
    ------{ xcsResetEventSem
    -------{ xlsResetEvent
    -------} xlsResetEvent rc=OK
    ------} xcsResetEventSem rc=OK
    -----} kqiWaitForABit rc=Unknown(5)
    
    Subsequent FDCs with a probe identifier of XC014030 and this
    call stack may also be seen:
    
     Comment1 :- Detected Corrupted Quickcell
     Comment2 :- 100886
    
    +---------------------------------------------------------------
    --------------+
    
    MQM Function Stack
    zlsMainThread
    zlsProcessMessage
    zlsProcessMQIRequest
    zlsMQCB
    zsqMQCB
    kpiMQCB
    kqiRegisterConsumer
    kqiAllocateWaiter
    xcsAllocateQuickCell
    xcsFFST
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Users of the IBM MQ asynchronous consume functionality may be
    affected by this problem
    
    
    Platforms affected:
    MultiPlatform
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    A flaw in the order of code meant that a waiting asynchronous
    MQGET may have been incorrectly made available to consume a
    message. This could lead to the consumer being posted to wake up
    when it should not have been.
    
    Being woken incorrectly led to the asynchronous consumer trying
    to access a piece of memory that had been freed.
    

Problem conclusion

  • The code was modified so that the asynchronous consumer would
    not be eligible to consume a message unless it was really able
    to do so.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v7.1       7.1.0.7
    v7.5       7.5.0.6
    v8.0       8.0.0.3
    
    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

    IV69571

  • Reported component name

    WMQ LIN X86 V7

  • Reported component ID

    5724H7224

  • Reported release

    710

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2015-02-17

  • Closed date

    2015-05-29

  • Last modified date

    2015-05-29

  • 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 LIN X86 V7

  • Fixed component ID

    5724H7224

Applicable component levels

[{"Line of Business":{"code":"LOB36","label":"IBM Automation"},"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSFKSJ","label":"WebSphere MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.1"}]

Document Information

Modified date:
08 March 2021