Public bug reported: 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's an issue with the transition to cgroup-v2, which on the ltp mailing list has been rumored that one of these days the tests would break. Its likely this was caused by a systemd update, switching to cgroup-v2 causing these tests to break due to different mount and cgroup hierarchy semantics. After setting systemd.unified_cgroup_hierarchy=0 on the kernel command line which sets cgroup back to v1, we get the expected failures that we saw in previous cycles, pointing to this not being a kernel regression. ** Affects: ubuntu-kernel-tests Importance: Undecided Status: New ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Tags: 5.13 hinted impish linux-kvm sru-20211018 ubuntu-ltp ubuntu-ltp-controllers ** Also affects: ubuntu-kernel-tests Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1949532 Title: ubuntu_ltp_controllers tests failing on Impish To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1949532/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs