RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:

Node Team on OpenShift received a report while testing OpenShift 4.13 that the RHEL 9.2 systemd is tainting the kernel when cgroupsv1 is enabled on the node. OpenShift and the Kernel Team will be supporting cgroupsv1 on OpenShift 4.13.

Version-Release number of selected component (if applicable):
RHEL 9.2

How reproducible:
Every time.

Steps to Reproduce:
1. Boots an OpenShift 4.13 node using cgroupsv1
2.
3.

Actual results:

Kernel is tainted.

Expected results:

Systemd should not taint cgroupsv1 enabled nodes on OpenShift 4.13.

Additional info:

Relevant code line:

https://github.com/systemd/systemd/blob/d685a5f6a4ae8f9eaea1d1c5c78171a915f3b16d/src/core/manager.c#L4728

Having this taint in place affects the results of the CNF certification tools like: https://github.com/test-network-function/test-network-function
Workload certifications won't pass if the platform is tainted. 

Thanks!

If you check the code, the manager only calls the function you have
mentioned here https://github.com/redhat-plumbers/systemd-rhel9/blob/main/src/core/manager.c#L3449
So, we only put a message into the logs. So, in the end, there is probably something else tainting the kernel.

[root@ci-vm-10-0-138-58 ~]# cat /proc/cmdline
BOOT_IMAGE=(hd0,msdos1)/boot/vmlinuz-5.14.0-306.el9.x86_64
root=UUID=462f9b3b-7b7e-4e25-beeb-ca2768fe9b47 ro rhgb quiet
crashkernel=1G-4G:192M,4G-64G:256M,64G-:512M net.ifnames=0
systemd.unified_cgroup_hierarchy=0

[root@ci-vm-10-0-138-58 ~]# journalctl --grep taint
May 09 04:50:08 localhost systemd[1]: System is tainted: cgroupsv1

[root@ci-vm-10-0-138-58 ~]# cat /proc/sys/kernel/tainted
0

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (systemd bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2023:6640