After upgrading to kernel 5.11, with cgroup v2 enabled, /dev/null is no longer writable in an LXD container and attempting to shutdown the container without --force hangs forever.
The /dev/null device does exist in the container with permissions crw-rw-rw-.
I’m using Fedora 33 where cgroup v2 is the default and it hasn’t been causing problems until now. Adding the following boot parameter fixes things:
systemd.unified_cgroup_hierarchy=0
Is anyone aware of a way to configure cgroup or LXD to allow access to /dev/null by the containers? I know virtually nothing about how cgroups work and didn’t find any obvious solution to fixing it.
Thanks.