Just verified that the 3 patches (bug description / SRU template) are included 
in kernel 4.19 and since 4.19 laded in disco proposed today, I'm changing the 
kernel entry to Fix Released (code is available in cosmic, too).
Changing project entry to Fix Released, too.

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

** Changed in: ubuntu-z-systems
       Status: Fix Committed => Fix Released

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https://bugs.launchpad.net/bugs/1799184

Title:
  [18.04 FEAT] zcrypt DD: introduce APQN tags to support deterministic
  driver binding

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

Bug description:
  == SRU Justification ==

  APQN tags in the zcrypt device driver are required to support
  deterministic driver binding

  With the introduction of KVM hw crypto virtualization (on s390x) the driver 
bound to an AP queue device is no longer unique determined.
  Therefore a deterministic hot plugging semantics of AP queues that may be 
bound to multiple drivers is needed.
  With the three listed commits here it will be possible to configure an AP 
queue (APQN) as being bound to a particular driver even if the associate hw 
gets intermittently lost and reconnected.

  == Fixes ==

  ac2b96f351d7d222 ("s390/zcrypt: code beautify")
  7e0bdbe5c21cb831 ("s390/zcrypt: AP bus support for alternate driver(s)")
  3d8f60d38e249f98 ("s390/zcrypt: hex string mask improvements for apmask and 
aqmask")

  == Patches ==

  Git-commit: ac2b96f351d7d222
  
https://github.com/torvalds/linux/commit/ac2b96f351d7d222c46e524feca03005f3fa8d75
  Author: Harald Freudenberger <fre...@linux.ibm.com>
  Date:   Fri Aug 17 12:36:01 2018 +0200
  s390/zcrypt: code beautify
  Code beautify by following most of the checkpatch suggestions:
   - SPDX license identifier line complains by checkpatch
   - missing space or newline complains by checkpatch
   - octal numbers for permssions complains by checkpatch
   - renaming of static sysfs functions complains by checkpatch
   - fix of block comment complains by checkpatch
   - fix printf like calls where function name instead of %s __func__
     was used
   - __packed instead of __attribute__((packed))
   - init to zero for static variables removed
   - use of DEVICE_ATTR_RO and DEVICE_ATTR_RW macros

  No functional code changes or API changes!

  Signed-off-by: Harald Freudenberger <fre...@linux.ibm.com>
  Signed-off-by: Martin Schwidefsky <schwidef...@de.ibm.com>

  ===

  Git-commit 7e0bdbe5c21cb831
  
https://github.com/torvalds/linux/commit/7e0bdbe5c21cb8316a694e46ad5aad339f6894a6
  Author: Harald Freudenberger <fre...@linux.ibm.com>
  Date:   Fri Jul 20 08:36:53 2018 +0200
  s390/zcrypt: AP bus support for alternate driver(s)
  The current AP bus, AP devices and AP device drivers implementation
  uses a clearly defined mapping for binding AP devices to AP device
  drivers. So for example a CEX6C queue will always be bound to the
  cex4queue device driver.

  The Linux Device Driver model has no sensitivity for more than one
  device driver eligible for one device type. If there exist more than
  one drivers matching to the device type, simple all drivers are tried
  consecutively.  There is no way to determine and influence the probing
  order of the drivers.

  With KVM there is a need to provide additional device drivers matching
  to the very same type of AP devices. With a simple implementation the
  KVM drivers run in competition to the regular drivers. Whichever
  'wins' a device depends on build order and implementation details
  within the common Linux Device Driver Model and is not
  deterministic. However, a userspace process could figure out which
  device should be bound to which driver and sort out the correct
  binding by manipulating attributes in the sysfs.

  If for security reasons a AP device must not get bound to the 'wrong'
  device driver the sorting out has to be done within the Linux kernel
  by the AP bus code. This patch modifies the behavior of the AP bus
  for probing drivers for devices in a way that two sets of drivers are
  usable. Two new bitmasks 'apmask' and 'aqmask' are used to mark a
  subset of the APQN range for 'usable by the ap bus and the default
  drivers' or 'not usable by the default drivers and thus available for
  alternate drivers like vfio-xxx'. So an APQN which is addressed by
  this masking only the default drivers will be probed. In contrary an
  APQN which is not addressed by the masks will never be probed and
  bound to default drivers but onny to alternate drivers.

  Eventually the two masks give a way to divide the range of APQNs into
  two pools: one pool of APQNs used by the AP bus and the default
  drivers and thus via zcrypt drivers available to the userspace of the
  system. And another pool where no zcrypt drivers are bound to and
  which can be used by alternate drivers (like vfio-xxx) for their
  needs. This division is hot-plug save and makes sure a APQN assigned
  to an alternate driver is at no time somehow exploitable by the wrong
  party.

  The two masks are located in sysfs at /sys/bus/ap/apmask and
  /sys/bus/ap/aqmask.  The mask syntax is exactly the same as the
  already existing mask attributes in the /sys/bus/ap directory (for
  example ap_usage_domain_mask and ap_control_domain_mask).

  By default all APQNs belong to the ap bus and the default drivers:

    cat /sys/bus/ap/apmask
    0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
    cat /sys/bus/ap/aqmask
    0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

  The masks can be changed at boot time with the kernel command line
  like this:

    ... ap.apmask=0xffff ap.aqmask=0x40

  This would give these two pools:

    default drivers pool:    adapter 0 - 15, domain 1
    alternate drivers pool:  adapter 0 - 15, all but domain 1
        adapter 16-255, all domains

  The sysfs attributes for this two masks are writeable and an
  administrator is able to reconfigure the assignements on the fly by
  writing new mask values into.  With changing the mask(s) a revision of
  the existing queue to driver bindings is done. So all APQNs which are
  bound to the 'wrong' driver are reprobed via kernel function
  device_reprobe() and thus the new correct driver will be assigned with
  respect of the changed apmask and aqmask bits.

  The mask values are bitmaps in big endian order starting with bit 0.
  So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
  attributes accept 2 different formats:
  - Absolute hex string starting with 0x like "0x12345678" does set
    the mask starting from left to right. If the given string is shorter
    than the mask it is padded with 0s on the right. If the string is
    longer than the mask an error comes back (EINVAL).
  - '+' or '-' followed by a numerical value. Valid examples are "+1",
    "-13", "+0x41", "-0xff" and even "+0" and "-0". Only the addressed
    bit in the mask is switched on ('+') or off ('-').

  This patch will also be the base for an upcoming extension to the
  zcrypt drivers to be able to provide additional zcrypt device nodes
  with filtering based on ap and aq masks.

  Signed-off-by: Harald Freudenberger <fre...@linux.ibm.com>
  Signed-off-by: Martin Schwidefsky <schwidef...@de.ibm.com>

  ===

  Git-commit 3d8f60d38e249f98
  
https://github.com/torvalds/linux/commit/3d8f60d38e249f989a7fca9c2370c31c3d5487e1
  Author: Harald Freudenberger <fre...@linux.ibm.com>
  Date:   Mon Aug 20 15:27:45 2018 +0200
  s390/zcrypt: hex string mask improvements for apmask and aqmask
  The sysfs attributes /sys/bus/ap/apmask and /sys/bus/ap/aqmask
  and the kernel command line arguments ap.apm and ap.aqm get
  an improvement of the value parsing with this patch:

  The mask values are bitmaps in big endian order starting with bit 0.
  So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
  attributes and the kernel command line accept 2 different formats:
   - Absolute hex string starting with 0x like "0x12345678" does set
     the mask starting from left to right. If the given string is shorter
     than the mask it is padded with 0s on the right. If the string is
     longer than the mask an error comes back (EINVAL).
   - Relative format - a concatenation (done with ',') of the terms
     +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]. <bitnr> may be any
     valid number (hex, decimal or octal) in the range 0...255.
     Here are some examples:
       "+0-15,+32,-128,-0xFF"
       "-0-255,+1-16,+0x128"

  Signed-off-by: Harald Freudenberger <fre...@linux.ibm.com>
  Signed-off-by: Martin Schwidefsky <schwidef...@de.ibm.com>

  == Regression Potential ==

  Mid to low, because:

  - There are quite some changes, but everything is limited to s390/zcrypt, 
means:
     arch/s390/include/uapi/asm/*
     and
     drivers/s390/crypto/*
  - So everything is s390x specific.
  - And larger parts of the changes are beautifications.
  - It's all upstream accepted in 4.19
  - The code is already successfully test, integrated and running in cosmic.

  == Test Case ==

  On an LPAR that has access to an CryptoExpress card,

  execute the 'lszcrypt --verbose'
  and check availability of:
  /sys/bus/ap/apmask

  General test and verification was already done by IBM.
  Please notice that the code already landed in cosmic.
  __________

  With the introduction of KVM crypto virtualization the driver bound to an AP 
queue device is no longer unique determined.
  This feature provides a deterministic hot plugging semantics of AP queues 
that may be bound to multiple drivers.
  In particular it enables to configure an AP queue (APQN) as being bound to a 
particular driver even if the associate HW gets intermittently lost and 
reconnected.

  This function has to be applied to kernel 4.15 for Ubuntu 18.04,

  Git Commit information available here:
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1784331

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