Description of problem:

Issuing systemctl daemon-reexec or systemctl daemon-reload removes all groups in blkio controller. Groups within other controllers (memory, freezer, pids) are preserved on reload or re-exec.

Possibly related to #2164049.

Version-Release number of selected component (if applicable):
v239-68.el8_7.4

How reproducible:
Always

Steps to Reproduce:

  cgcreate -g blkio:test
  cgcreate -g memory:test
  ll /sys/fs/cgroup/{blkio,memory}/test/cgroup.procs
  systemctl daemon-reload
  ll /sys/fs/cgroup/{blkio,memory}/test/cgroup.procs

Actual results:

-rw-rw-r-- 1 root root 0 Mar  1 18:10 /sys/fs/cgroup/blkio/test/cgroup.procs
-rw-rw-r-- 1 root root 0 Mar  1 17:49 /sys/fs/cgroup/memory/test/cgroup.procs

ls: cannot access '/sys/fs/cgroup/blkio/test/cgroup.procs': No such file or directory
-rw-rw-r-- 1 root root 0 Mar  1 17:49 /sys/fs/cgroup/memory/test/cgroup.procs

Expected results:

-rw-rw-r-- 1 root root 0 Mar  1 18:10 /sys/fs/cgroup/blkio/test/cgroup.procs
-rw-rw-r-- 1 root root 0 Mar  1 17:49 /sys/fs/cgroup/memory/test/cgroup.procs

-rw-rw-r-- 1 root root 0 Mar  1 18:10 /sys/fs/cgroup/blkio/test/cgroup.procs
-rw-rw-r-- 1 root root 0 Mar  1 17:49 /sys/fs/cgroup/memory/test/cgroup.procs

Additional info:

Downgrading to v239-68.el8_7.2 preserves expected behavior. Running cgconfig service to apply custom groups preserves hierarchy until next reload or re-exec issuance.