Container stopped working

Hello,

Have exactly the same issue after upgrade from 3.21 to 3.22 (on arm64). Tried both versions from snap (rev 13718 3.22/stable and rev 13764 3.22/candidate).

Inside containers I see only 1 process init:

root@ns01:~# ps aux
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root         1  0.0  0.0  12116  3068 ?        Ss   14:13   0:00 /sbin/init
root       205  0.0  0.0   7300  3364 ?        Ss   14:13   0:00 bash
root       215  0.0  0.0   8680  2764 ?        R+   14:13   0:00 ps aux

In logs:

systemd 237 running in system mode. (+PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD -IDN2 +IDN -PCRE2 default-hierarchy=hybrid)
Detected virtualization lxc.
Detected architecture arm64.

Welcome to Ubuntu 18.04.1 LTS!

Set hostname to <ns01>.
Failed to create compat systemd cgroup /lxc.payload/ns01/init.scope: Invalid argument
Failed to attach 1 to compat systemd cgroup /lxc.payload/ns01/init.scope: No such file or directory
Failed to open pin file: No such file or directory
Failed to allocate manager object: No such file or directory
[ESC[0;1;31m!!!!!!ESC[0m] Failed to allocate manager object, freezing.
Freezing execution.

Set to “security.privileged” and server reboot didn’t help.