Comment 8 for bug 1557776

@BradFigg,
on ubuntu 16.04 it isn't set to y:
grep AUFS_X /boot/config-4.4.0-21-generic
# CONFIG_AUFS_XATTR is not set

You can check whether the problem with docker still persists by running this:
docker run --rm -ti centos:7 yum install -y httpd

Right now it fails with:
error: unpacking of archive failed on file /usr/sbin/suexec: cpio: cap_set_file