You have been subscribed to a public bug:

SRU Justification:
==================

[Impact]

 * If multiple s390x crypto domains are available,
   the output of all domains does no longer fit into the output buffer of one 
CHSC call.

 * Thus, the response contains a partial-response-snippet that indicates
that there is more data to be retrieved.

 * The remaining data is then retrieved in a subsequent CHSC call,
   but there is an error in zcryptstats in populating the request with the next 
domain number to obtain data for.

 * This results in the fact that it retrieves the data for domains 1 to n over 
and over again,
   and always gets the partial-response snippet, hence this loops indefinitely.

[Test Case]

 * An Ubuntu Server 20.04 system (or newer) is needed on z/VM or LPAR
with two or more crypto domains accessible.

 * Now call 'zcryptstats --all -V' and verify if the command completes
successfully (within seconds) or hangs (loops).

[Where problems could occur]

 * The patch fixes the code that passes the correct next-domain to the
subsequent CHSC call of a partial response.

 * In case done wrong even no data at all from any of the domains is
retrieved,

 * or the tool may even try to retrieve data from a domain that has an
invalid index, which will lead to an error (the rc is captured).

 * But the code changes are marginal and pretty straight forward, and
the cases where scdmd_area.request.first_drid is handled are now
enclosed by proper 'if/else' statement.

 * This patch was already upstream accepted and a patched s390-tools package 
was build and shared in a PPA for further testing.
__________
---Problem Description---
I have had trouble collecting data via the zcryptstats 
(https://github.com/ibm-s390-tools/s390-tools/blob/master/zconf/zcrypt/zcryptstats.c)
 tool for our Hosting Appliance - VPC environment. Basically, the tool reports 
data for only the last two domain IDs. Further, it hangs if I collect data for 
a complete crypto card, and then I have to kill the ssh session to get back.

strace attached, ltrace not available and can't be installed due to no
Internet access.

===================

Addl. Information:

This seems to be a problem with the handling of partial responses of the
SCDMD CHSC command.

When many domains are available, then the output of all domains does not
fit into the output buffer of one CHSC call. Thus, the response contains
a partial-response-bit that indicates that there is more data to be
retrieved. This is done in a subsequent CHSC call, but there is an error
in zcryptstats with populating the request with the next domain number
to obtain data for. This results in the fact that it retrieves the data
for domains 1 to n over and over again, and always gets the partial-
response bit set. So this loops forever.

===================
The fix for this in now upstream:
https://github.com/ibm-s390-tools/s390-tools/commit/cf2311f1f1de17435b49ba8c8697be91705ba031

This need to be integrated in all Ubuntu distros, from 20.04 on. F/G/H

** Affects: ubuntu-translations
     Importance: Undecided
     Assignee: Skipper Bug Screeners (skipper-screen-team)
         Status: Invalid

** Affects: ubuntu-z-systems
     Importance: Medium
     Assignee: Skipper Bug Screeners (skipper-screen-team)
         Status: Triaged

** Affects: s390-tools (Ubuntu)
     Importance: Medium
         Status: Fix Committed

** Affects: s390-tools (Ubuntu Focal)
     Importance: Medium
     Assignee: Frank Heimes (fheimes)
         Status: Triaged

** Affects: s390-tools (Ubuntu Groovy)
     Importance: Medium
     Assignee: Frank Heimes (fheimes)
         Status: Triaged

** Affects: s390-tools (Ubuntu Hirsute)
     Importance: Medium
         Status: Fix Committed


** Tags: architecture-s39064 bugnameltc-189183 patch severity-medium 
targetmilestone-inin2004
-- 
[UBUNTU 20.04] Cannot run zcryptstats in the Hosting Appliance
https://bugs.launchpad.net/bugs/1903984
You received this bug notification because you are a member of Ubuntu 
Translations Coordinators, which is subscribed to Ubuntu Translations.

_______________________________________________
Mailing list: https://launchpad.net/~ubuntu-translations-coordinators
Post to     : ubuntu-translations-coordinators@lists.launchpad.net
Unsubscribe : https://launchpad.net/~ubuntu-translations-coordinators
More help   : https://help.launchpad.net/ListHelp

Reply via email to