Partial cgroupfs causing troubles with k3d

Support Kernel
1

Version info:
kernel 5.12.2, 5.11.19,
systemd 248.2-1.1

I ran into a trouble with cgroupfs which I currently can not solve myself. So far all materials I found miss my case, which is - I do have /proc/sys/fs/cgroup, but not ‘cpuset’ and other nodes. This causes k3d/k3s to fail while launching their containers. Docker itself still works.

I did compare results between xps laptop and desktop. My desktop has only

$ mount|grep cgr
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)

$ k3s check-config

....
Generally Necessary:
- cgroup hierarchy: **nonexistent??** (fail)
    (see https://github.com/tianon/cgroupfs-mount)

My laptop brings more, and k3s works there flawlessly:

$ mount|grep cgr
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,size=4096k,nr_inodes=1024,mode=755,inode64)
cgroup2 on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,name=systemd)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)

I suspect troubles with some systemd or kernel options, but from quick look at units which are running on both nodes I don’t see any indicator which should or could affect cgroups handling.
From arch wiki materials I know there are troubles with different modes of cgroups handling, however I am not willing to tinker this unless I get proper mounts.

Can anyone share any tips how to force cpuset mounts? Systemd docs focuses mainly on settings for units, but not mounts itself.

2

Solved through making extra arg for grub in /etc/default/grub:

GRUB_CMDLINE_LINUX="systemd.unified_cgroup_hierarchy=0"

It is still unclear to me why this did happen on my desktop since it has the same core packages as laptop. Yet, I will not dive more into it given above workaround works.

Edit… in the end it was all because my root partition was based on f2fs. It trurns out that k3s/kubernetes does not work properly witch such filesystem despite of no issues reported by docker itself.
I had to move /var/lib/docker to partition formatted with ext4. Only then it moved ahead. So if any of you experience troubles with running kubernetes on your dev box - double check filesystem. Relocation did the trick.