Failed to build image in Concourse due to readonly fs

[dmytro-zhernosiekov-rft]

Hi,
Updated Concourse to 6.7.5 version and enabled containerd. Just after that was not able to build image with oci-build-task.
Here is code:

jobs:
- name: build-docs
  plan:
  - get: docs-git
    trigger: true
  - task: build-docs-container
    privileged: true
    config:
      platform: linux
      image_resource:
        type: registry-image
        source:
          repository: vito/oci-build-task
      caches:
      - path: cache
      inputs:
      - name: docs-git
      outputs:
      - name: image
      params:
        CONTEXT: docs-git
      run:
        path: build

This code was ok on 6.7.2 concourse and after upgrade to 6.7.5 Concourse and enable containerd I got this error:

#10 0.077 container_linux.go:367: starting container process caused: process_linux.go:340: applying cgroup configuration for process caused: mkdir /sys/fs/cgroup/cpuset/buildkit: read-only file system
#10 ERROR: executor failed running [/bin/sh -c apk -q add gcc musl-dev]: exit code: 1

It just try to install some packages in alpine image.
I found that this topic was discussed in concourse github issue and it looked like /dev/shm size. I checked our Concourse worker setup and there are already 64Mb assigned to shared memory.

Could you looks at this issue?

What I found:
concourse/concourse#6348
#38

[sl304227-nh]

This problem went away when I upgraded to 7.X