https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1942113

Here is a discussion about recent regressions in systemd tests where its
stated that the cgroups are set up in "unified" (v2) mode in
248.3-1ubuntu5 systemd package. 248.3-1ubuntu7 became the release
package on 2021-09-27 which was around the start of the cycle that we
started seeing this issues (did we see this before then?), which means
that it could very likely have been this upgrade that caused it. Even if
earlier packages were in updates I am pretty sure that the machine needs
to be restarted for the systemd changes to take affect, which I am
pretty sure our test machines don't restart after updating during
deployment. So it would make sense that we are seeing the errors
correlating with the new systemd package hitting release.

I also re-ran tests on previous kernels which didnt have these issues
and they are now reporting all the errors, which also points to this
being a problem with the systemd package upgrade.

In the meantime, it seems that these tests are broken and we should just
hint the whole ubuntu_ltp_controllers test suite.

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1949532

Title:
  ubuntu_ltp_controllers tests failing on Impish

Status in ubuntu-kernel-tests:
  New
Status in linux package in Ubuntu:
  Incomplete

Bug description:
  Almost half of the ubuntu_ltp_controllers tests are failing due to the
  general pattern 'cgroup_name already mounted or mount point busy'
  causing the tests to fail.

  e.g.
  mount: /dev/cgroup: ltp_cgroup already mounted or mount point busy.
  cgroup_fj_function2_memory 1 TBROK: mount -t cgroup -o memory ltp_cgroup 
/dev/cgroup failed

  From investigation it seems there could be an issue with the
  transition to cgroup-v2. There have been rumors on the ltp mailing
  list that one of these days the tests could break due to the
  transition. Switching to cgroup-v2, likely due to a systemd update,
  could cause these tests to break due to different mount and cgroup
  hierarchy semantics.

  I could only reproduce a subset of the new failures we are seeing, but
  after setting systemd.unified_cgroup_hierarchy=0 on the kernel command
  line which sets cgroup back to v1, a lot of the failures I could
  produce went away.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1949532/+subscriptions


-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to