Changed disco entry to Fix Released according to comment #3.

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

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https://bugs.launchpad.net/bugs/1818854

Title:
  [Ubuntu] vfio-ap: add subsystem to matrix device to avoid libudev
  failures

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

Bug description:
  SRU Justification:

  [Impact]

  * The vfio-ap driver will create a matrix device in sysfs without a
  subsystem link.

  * This causes failures in libudev that might also lead to libvirt
  errors.

  * A fix is upstream in master branch for kernel 5.1

  [Fix]

  * 36360658eb5a6cf04bb9f2704d1e4ce54037ec99 3636065 "s390: vfio_ap:
  link the vfio_ap devices to the vfio_ap bus subsystem"

  [Test Case]

  * An s390x machine with at least one CryptoExpress card,
    where at least one AP and one 'Domain' is assigned to a particular LPAR.

  * Now running virsh nodedev-list before (and later after) construction
  the matrix device should expose the issue.

  * For details about how to setup a vfio-ap matrix device see: 
http://kvmonz.blogspot.com/2018/12/qemu-v31-released.html
    (see 2nd bullet: virtio-ap)

  [Regression Potential]

  * The regression potential can be considered as low since it only
  affects the s390x platform

  * and there it only affects the usage of AP (CryptoExpress) cards and
  it's driver/module

  * and again only affects the recently introduced virtual IO function
  of AP (vfio-ap).

  [Other Info]

  * It was already briefly discussed here:
    https://www.redhat.com/archives/libvir-list/2019-February/msg00837.html
    as well as reviewed and pushed.

  * Commit 3636065 from v5.1-rc1

  * This affects ccw cards and their vf only, NOT vf of PCI/PCIe cards!

  * For details on virtio-ap/vfio-ap see bullet #2 here: 
http://kvmonz.blogspot.com/2018/12/qemu-v31-released.html
  _________________________

  ---Problem Description---
  The vfio-ap driver will create a matrix device in sysfs without a subsystem 
link. This triggers failures in libudev that might also lead to libvirt errors 
(e.g. see 
https://www.redhat.com/archives/libvir-list/2019-February/msg00837.html)

  The proper fix is to add a subsystem link (e.g. by providing a dummy
  bus).

  A fix for that is upstream in master branch already for kernel 5.1

  
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=36360658eb5a6cf04bb9f2704d1e4ce54037ec99

  This  need to be applied to Bionic, Cosmic and Disco

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