I'm changing the status of the "linux (Ubuntu)" entry - which represents 
'focal' the current release in development - to Fix Released, since patch 
"s390/idle: fix cpu idle time calculation" with commit ID "3d7efa4" landed in 
focal with the update of focal's kernel to 5.4 ( as of today).
This patch is in:

** Changed in: linux (Ubuntu)
       Status: Confirmed => Fix Released

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  [UBUNTU] kernel: cpu idle time calculation

Status in Ubuntu on IBM z Systems:
  Fix Committed
Status in linux package in Ubuntu:
  Fix Released
Status in linux source package in Bionic:
  Fix Committed
Status in linux source package in Disco:
  Fix Committed
Status in linux source package in Eoan:
  Fix Committed

Bug description:
  Description:   kernel: cpu idle time calculation
  Symptom:       The cpu idle time reported within /proc/stat as well as in
                 /sys/devices/system/cpu/cpuX/idle_time_us sometimes may
                 show incorrect values.
  Problem:       The kernel tries to figure out when a cpu entered idle
                 by accessing its per-cpu data structure. There is an
                 ordering problem: if a remote cpu has an idle_enter
                 value which is not zero, and an idle_exit value which
                 is zero, it is assumed it is idle since "now". The
                 "now" timestamp however is taken before the idle_enter
                 value is read.
                 This in turn means that "now" can be smaller than
                 idle_enter of the remote cpu. Unconditionally
                 subtracting idle_enter from "now" can thus lead to a
                 negative value (aka large unsigned value).
  Solution:      Move the get_tod_clock() invocation.


  Patch tagged as "stable".

  Tracking the integration of this patch in the relevant distros..

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