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VM66819: Z/VM 7.4 CP: FIX PACK - FEATURE 00 FIX 06

A fix is available

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • This APAR contains required service for z/VM version 7 release
    4.
    

Local fix

  • N/A
    

Problem summary

  • ****************************************************************
    
    * USERS AFFECTED: All users of z/VM                            *
    
    ****************************************************************
    
    * PROBLEM DESCRIPTION:                                         *
    
    ****************************************************************
    
    * RECOMMENDATION: APPLY PTF                                    *
    
    ****************************************************************
    
    This is the APAR for z/VM 7.4 Fix Pack 6. It contains fixes for
    the following three problems:
    
    Problem 1:
    GUEST RELOCATION INCOMPATIBILITY
    
    Live guest relocation (LGR) errors can occur for guests in
    certain hardware migration scenarios when introducing new
    versions of IBM Z hardware. This is due to a potential
    change in a value returned by the hardware which is used
    to determine the architecture level for associated guests.
    
    -----
    
    Problem 2:
    UNPLANNED HYPERSWAP ON SUBCHANNEL OFFLINE DEVICE
    
    Unnecessary HyperSwap auto-quiesce swap trigger is taken during
    a z/VM host initiated I/O request to a subchannel offline
    (SUBCHOFF) device.  The I/O error received in this state is not
    due to a hardware problem on the associated device but simply
    because of the architected state of the device at the time.  No
    unplanned swap should take place due to such an event.
    
    -----
    
    Problem 3:
    PRG006 ENCOUNTERED DUE TO IMPROPER INSTRUCTION INPUT
    
    CP abends with a PRG006 when an incorrect input is issued on a
    confidential instruction. The fix, related to base code,
    corrects the input and CP does not abend. Those with guests
    attached to integrated consoles, that are likely sick, may
    be affected.
    

Problem conclusion

  • Problem 1:
    GUEST RELOCATION INCOMPATIBILITY
    
    Internal handling of the architected value of interest was
    updated to prevent the relocation errors related to
    potential architectural incompatibility introduced to the guest.
    
    
    This fix should be applied on all members of an SSI cluster
    to avoid potential live guest relocation compatibility issues.
    If not applied concurrently across an SSI cluster, use of the
    FORCE ARCHITECTURE option of the VMRELOCATE command may be
    required to relocate guests to updated members.
    
    -----
    
    Problem 2:
    UNPLANNED HYPERSWAP ON SUBCHANNEL OFFLINE DEVICE
    
    To ensure this incorrect HyperSwap trigger no longer occurs,
    a set of changes were made to improve the CC3 error recovery
    path and prevent subchannel offline (SUBCHOFF) devices from
    persisting in a GDPS environment enabled for HyperSwap
    auto-quiesce. - CC3 error recovery was updated to no longer
    create SVM
      records for GDPS if the affected device is SUBCHOFF.
    - HYPERSWAP ENABLE was updated to issue new message HCP6434I
      to indicate that SUBCHOFF devices cannot be enabled for
      HyperSwap auto-quiesce.
    - VARY OFF SUBCHannel was updated to also turn off the
      HyperSwap enabled indicator for the specified device. This
      prevents a device previously enabled for HyperSwap from
      entering into an unsupported state for HyperSwap. GDPS will
      recognize this change for the device and report the
      configuration error to the end user.
    - Query DASD DETAILS was updated to no longer issue I/O
      requests when the specified device is found in the SUBCHOFF
      state. The external response (I/O Error) in portions of the
      query response remains the same without making an I/O request
      which cannot complete successfully.
    
    -----
    
    Problem 3:
    PRG006 ENCOUNTERED DUE TO IMPROPER INSTRUCTION INPUT
    
    Once it was discovered the wrong input was being passed to the
    failing instruction, the input was fixed. The problem situation
    was recreated with and without the fix to ensure the abend was
    avoided.
    

Temporary fix

  • FOR RELEASE VM/ESA CP/ESA R740 :
    PREREQ: VM66815
    CO-REQ: NONE
    IF-REQ: NONE
    

Comments

APAR Information

  • APAR number

    VM66819

  • Reported component name

    VM CP CP

  • Reported component ID

    568411202

  • Reported release

    740

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2025-01-15

  • Closed date

    2025-01-31

  • Last modified date

    2025-07-18

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    UM90502

Modules/Macros

  • HCPARD   HCPCPE   HCPCPK   HCPERR   HCPIOJ   HCPMES   HCPMESB
    HCPMXRBK HCPPCB   HCPQDE   HCPZCP   HCP6434I HYPERSWA SUBCHANN
    7VMCPR40
    

Publications Referenced
SC24626873GC24627073   

Fix information

  • Fixed component name

    VM CP CP

  • Fixed component ID

    568411202

Applicable component levels

  • R740 PSY UM90502

       UP25/01/31 P 2501

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

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Document Information

Modified date:
18 July 2025