Your filesystem or build does not support posix ACLs, which s3fs requires. Try the mounting the filesystem with the 'acl' option."
I got this error while trying to run the provision step during the configuration of Samba4. I tried remounting my root file system with acl but still the provision step was throwing this error. Finally I got a workaround for this which I thought should share for others as well.
Use extra argument along with the provision command as shown below
# samba-tool domain provision --use-interactive --use-ntvfs
Let me know your success and failures