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Fix CPU-MF error on new IBM Z Hardware by adding support for CPU-MF
counter second version 7

Error Symptom: Daemon cpacfstatsd fails on start up of the system 
               with this error message
               cpacfstatsd: Event DEA_FUNCTIONS for pmu cpum_cf
                            not found (2:No such file or directory)
Problem:       When the CPU Measurement facility device driver
               is initialized during kernel boot, it reads out the
               CPU Measurement facility counter hardware first and 
               second version numbers. Depending on these numbers
               the device driver exports attributes in the sysfs
               directory /sys/devices/cpum_cf/events. When the
               CPM-MF second version number is not known, no
               attributes of the crypto counter set are exported.
               However the cpacfstatsd program scans the sysfs
               directory /sys/devices/cpum_cf/events for attribute
               files of the crypto counter set, for example attribute
               file DEA_FUNCTIONS and others.
Solution:      Add support for the new CPU-MF Measurement counter
               facility second version number 7. This number then
               exports the crypto counter set in directory
               directory /sys/devices/cpum_cf/events.
               Also add support for limited samples. These hardware
               samples contain all zeroes and are of no value when
               using the CPU Measurement Facility sampling hardware.
               Drop these samples when the limited sampled bit is set
               in the sample descriptor.
Reproduction:  Run command ls -l /sys/devices/cpum_cf/events |
                  fgrep DEA
                     DEA_BLOCKED_CYCLES
                     DEA_BLOCKED_FUNCTIONS
                     DEA_CYCLES
                     DEA_FUNCTIONS
               When there is no output at all the attributes files
               for the crypto counter set have not been exported.
               If above output is visible, the described problem does
               not show up.
Upstream-ID:   a87b0fd4f9003f8521226e226cf92b18147b3519
               745f5d20e7936931f924410f32d8b0e599b5990e
Problem-ID:    196017

Preventive:    yes
Reported:      Christian Rund <christian.r...@de.ibm.com>
SupportTicket: -
Reference:     -
Date:          2022-01-20
Author:        Thomas Richter <tmri...@linux.ibm.com>
Component:     kernel

** Affects: linux (Ubuntu)
     Importance: Undecided
     Assignee: Skipper Bug Screeners (skipper-screen-team)
         Status: New


** Tags: architecture-s39064 bugnameltc-196340 severity-high 
targetmilestone-inin---
-- 
[UBUNTU 20.04] kernel: Add support for CPU-MF counter second version 7
https://bugs.launchpad.net/bugs/1960182
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