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[Nick Rosbrook <2103414@xxxxxxxxxxxxxxxxxx>]

It seems the test plan is missing a step where you actually check that
libutils reports the correct machine name, and not "Unknown machine
type". Can you please expand the test plan to cover that?

Or, if I am misunderstanding the existing plan, please elaborate how
that is already covered?

** Changed in: s390-tools (Ubuntu Noble)
       Status: In Progress => Incomplete

** Changed in: s390-tools (Ubuntu Plucky)
       Status: In Progress => Incomplete

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https://bugs.launchpad.net/bugs/2103414

Title:
  [25.04 FEAT] [post announcement] [KRN2304] CPU-MF Counters for new IBM
  Z hardware - s390-tools part

Status in Ubuntu on IBM z Systems:
  In Progress
Status in s390-tools package in Ubuntu:
  Fix Released
Status in s390-tools-signed package in Ubuntu:
  Fix Released
Status in s390-tools source package in Noble:
  Incomplete
Status in s390-tools-signed source package in Noble:
  Triaged
Status in s390-tools source package in Plucky:
  Incomplete
Status in s390-tools-signed source package in Plucky:
  In Progress
Status in s390-tools source package in Questing:
  Fix Released
Status in s390-tools-signed source package in Questing:
  Fix Released

Bug description:
  [ Impact ]

   * A new IBM Z hardware generation (z17) was recently introduced.
     
   * Hence s390-tools' libutil needs to be aware of the new hardware
     name (z17, z17_2) and it's new type(s) (9175, 9176) to be able
     to identify and map type to name and vice versa.

   * This is especially needed to map new CPU management facility (MF)
     hardware counters to the correct hardware name and type.

   * Without patching, new z17 hw, i.e. if referenced in CPU MF
     (or other cases) by it's new machine type, would be reported
     by libutils as "Unknown machine type".

  [ Test Plan ]

   * Prepare an IBM z17 LPAR with Ubuntu 25.04
     (incl. this s390-tools patch and the commit above for the kernel).

   * At LPARs activation profile, navigate to the Security page
     and within the counter facility options, select each counter set
     you want to use. (One may just select all for testing purposes.)

   * Use 'perf list' to determine if the new counters are listed.
     (Cmd 'ls -l /sys/devices/cpum_cf/events | wc -l' needs to report 106 on z17.)

   * For comparing the new counters (and their names) see:
     dc7cafd91cba ("s390/cpumf: Update CPU Measurement facility extended
     counter set support")
     https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/\
     plucky/commit/?h=master-next&id=dc7cafd91cba63b200f33ced7530b1d76a2b5495

   * Use 'perf stat -e' to enable and make use of these counters.

  [ Fix ]

   * b3db52fd165e6a26d9c73e51bd5322b55017ef94
     ("libutil: Add machine type definition for machines 9175 and 9176")

   * Nobel misses the type for an intermediate/updated model
     ('Z16_A02' on top of Z16)
     thus I'm adding this first (needed for noble only) as a pre-requirement.
     ef1799f31fa2a11467373077058b8b5a3838c4b1
     ("s390-tools/libutil: Add machine type 3932")

  [ Where problems could occur ]

   * The patch is pretty straight forward, but there can always be problems,
     be it a 'slip of the pen' or a typo, with that:

   * The names or type information could be wrong, which could lead
     to an incorrect identification (or not identification) of a z17 system.

   * The new case statements might not be inserted correctly
     or not correctly closed/terminated,
     which might lead again to an incorrect identification
     or to "Unknown machine type".

   * The above could again lead to:
     - incorrect event exposure on unsupported hardware
     - invalid perf measurements
     - sysfs inconsistencies
     - or warnings due to misconfigured or non-existent counters

   * Only new code is added by this commit - none is changed nor
  removed.

   * These CPU MF counters and their handling is unique to s390x,
     hence no other architectures are be affected.

  [ Other Info ]

   * The CPU MF hw counters themselves are part of the kernel:
     dc7cafd91cba ("s390/cpumf: Update CPU Measurement facility extended
     counter set support") and are handled in kernel SRU LP#2114258.

   * Hence there is no harm to have the support in s390-tools before having
     in the kernel, since in this case the new type info will just not be used.
     In case the kernel has support first and libutils is used,
     libutil will report "Unknown machine type".
  __________

  Feature Description:

  Support for CPU-MF counters of new IBM Z hardware in kernel,
  s390-tools, perf (kernel) and libpfm4.

  This part covers the s390-tools changes to lscpumf and libutil.

  The related patches / commit IDs will be provided as soon as the
  required information has been publicly disclosed.

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