IBM Support

IT29281: MQ process hang after memory exception SIGSEGV

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APAR status

  • Closed as program error.

Error description

  • A queue manager process (for example, amqrmppa) did not respond
    after receiving a memory exception (SIGSEGV) and a partial
    failure data capture (FDC) record was generated.
    

Local fix

Problem summary

  • ****************************************************************
    USERS AFFECTED:
    Users of MQ in the unlikely event that a memory exception is
    generated within heap management routines (a possible cause of
    this is corruption of the heap memory).
    
    
    Platforms affected:
    AIX, Linux on Power, HP-UX Itanium, Solaris x86-64, Solaris
    SPARC, Linux on zSeries, Linux on x86-64, Linux on x86, IBM
    iSeries
    
    ****************************************************************
    PROBLEM DESCRIPTION:
    To obtain information about the process, the MQ signal handler
    had called the C library function fopen() marked as
    non-async-signal-safe.  This caused a secondary memory
    exception, whose signature was a partially-written FDC record
    and the process did not respond after the exception.
    

Problem conclusion

  • The call to fopen() to obtain information about the process has
    been moved to earlier in the life of the program, so that it is
    not called from the signal handler.
    
    ---------------------------------------------------------------
    The fix is targeted for delivery in the following PTFs:
    
    Version    Maintenance Level
    v8.0       8.0.0.14
    v9.0 LTS   9.0.0.8
    v9.1 CD    9.1.4
    v9.1 LTS   9.1.0.4
    
    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 number

    IT29281

  • Reported component name

    WMQ BASE MULTIP

  • Reported component ID

    5724H7241

  • Reported release

    750

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2019-05-28

  • Closed date

    2019-09-30

  • Last modified date

    2020-04-15

  • 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

    5724H7241

Applicable component levels

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSCPQ63","label":"APAR \/ Maintenance"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
16 April 2020