[7.2.0] Error starting worker - btrfs command

Hi there I'm trying to bring up concourse with the docker-compose file but its failing to bring up the worker

{
   "timestamp":"2021-04-28T13:24:16.201601866Z",
   "level":"error",
   "source":"baggageclaim",
   "message":"baggageclaim.fs.run-command.failed",
   "data":{
      "args":[
         "bash",
         "-e",
         "-x",
         "-c",
         "\n\t\tif [ ! -e $IMAGE_PATH ] || [ \"$(stat --printf=\"%s\" $IMAGE_PATH)\" != \"$SIZE_IN_BYTES\" ]; then\n\t\t\ttouch $IMAGE_PATH\n\t\t\ttruncate -s ${SIZE_IN_BYTES} $IMAGE_PATH\n\t\tfi\n\n\t\tlo=\"$(losetup -j $IMAGE_PATH | cut -d':' -f1)\"\n\t\tif [ -z \"$lo\" ]; then\n\t\t\tlo=\"$(losetup -f --show $IMAGE_PATH)\"\n\t\tfi\n\n\t\tif ! file $IMAGE_PATH | grep BTRFS; then\n\t\t\tmkfs.btrfs --nodiscard $IMAGE_PATH\n\t\tfi\n\n\t\tmkdir -p $MOUNT_PATH\n\n\t\tif ! mountpoint -q $MOUNT_PATH; then\n\t\t\tmount -t btrfs -o discard $lo $MOUNT_PATH\n\t\tfi\n\t"
      ],
      "command":"/bin/bash",
      "env":[
         "PATH=/usr/local/concourse/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
         "MOUNT_PATH=/worker-state/volumes",
         "IMAGE_PATH=/worker-state/volumes.img",
         "SIZE_IN_BYTES=4817158144"
      ],
      "error":"exit status 1",
      "session":"3.1",
      "stderr":"+ '[' '!' -e /worker-state/volumes.img ']'\n+ touch /worker-state/volumes.img\n+ truncate -s 4817158144 /worker-state/volumes.img\n++ losetup -j /worker-state/volumes.img\n++ cut -d: -f1\n+ lo=\n+ '[' -z '' ']'\n++ losetup -f --show /worker-state/volumes.img\nlosetup: /worker-state/volumes.img: failed to set up loop device: No such file or directory\n+ lo=\n",
      "stdout":""
   }
}

To get round it I changed the driver to be detect (I commented it out to get the error again)

Happy to PR if you think that should be the default for the docker-compose file

I'm running centos 7 running 5.7.10-1

Thanks

Gary

concourse / concourse-docker

[7.2.0] Error starting worker - btrfs command #69