qa-regression-testing test_ulimit_stack_small fails on ppc64el/i386

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1814295

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

Found on T-LTS-X i386 as well.

BTW this test has been disabled for PPC

       if self.dpkg_arch == 'ppc64el':
            '''https://bugs.launchpad.net/bugs/1814295'''
            return self._skipped('WARN: intermittent failures on ppc64el (LP: #1814295)')

Hrm, I am unable to reproduce this on i386 in either trusty with lts-xenial or in xenial directly, despite attempting to reproduce the test failure repeatedly.

Hello,
It looks like this is a bit flaky for i386,
I can see this failure with 4.18.0-19.20~18.04.1-generic on i386 node "onza", fail rate 2 out of 3 attempts.

======================================================================
FAIL: test_ulimit_stack_small (__main__.KernelNonSecurityTest)
Ensure small stack limits are enforced
----------------------------------------------------------------------
Traceback (most recent call last):
  File "./test-kernel-security.py", line 2896, in test_ulimit_stack_small
    self.assertShellExitIn(expected, self._unpriv_cmd(["sh", "-c", "ulimit -s 1 && /bin/true"]))
  File "/home/ubuntu/autotest/client/tmp/ubuntu_qrt_kernel_security/src/qa-regression-testing/scripts/testlib.py", line 1151, in assertShellExitIn
    self.assertIn(rc, expected, msg + result + report)
AssertionError: Got exit code 0, expected one of 139
Command: 'sudo', '-u', 'ubuntu', 'sh', '-c', 'ulimit -s 1 && /bin/true'
Output:

Found on 5.0 B-hwe i386 with node pepe.

Issue found on 4.4.0-167.196~14.04.1 with node onza.

Issue found on 4.4.0-178.208~14.04.1 with node onza.

Issue found on Precise 3.2 i386 3.2.0-145.192

Still see this sometimes pop up, currently found on Bionic/linux 4.15.0-144.148 i386. found via ADT

  Kernel correctly calls access_ok on compat_alloc_userspace (CVE-2010-3081) ... ok

  ======================================================================
  FAIL: test_ulimit_stack_small (__main__.KernelNonSecurityTest)
  Ensure small stack limits are enforced
  ----------------------------------------------------------------------
  Traceback (most recent call last):
    File "./test-kernel-security.py", line 3002, in test_ulimit_stack_small
      self.assertShellExitIn(expected, self._unpriv_cmd(["sh", "-c", "ulimit -s 1 && /bin/true"]))
    File "/tmp/autopkgtest.Q9nQbe/build.SKg/src/autotest/client/tmp/ubuntu_qrt_kernel_security/src/qa-regression-testing/scripts/testlib.py", line 1181, in assertShellExitIn
      self.assertIn(rc, expected, msg + result + report)
  AssertionError: Got exit code 0, expected one of 139
  Command: 'sudo', '-u', 'ubuntu', 'sh', '-c', 'ulimit -s 1 && /bin/true'
  Output:

  ----------------------------------------------------------------------
  Ran 125 tests in 51.673s

  FAILED (failures=1)
15:17:45 INFO | END ERROR ubuntu_qrt_kernel_security.test-kernel-security.py ubuntu_qrt_kernel_security.test-kernel-security.py timestamp=1621610265 localtime=May 21 15:17:45