The root.log of F25 build jobs prints this late:
DEBUG util.py:421: Running transaction
DEBUG util.py:421: /var/tmp/rpm-tmp.W2zvnF: line 1: udevadm: command not found
DEBUG util.py:421: /var/tmp/rpm-tmp.W2zvnF: line 2: udevadm: command not found
DEBUG util.py:421: Running in chroot, ignoring request.
Haven't done anything to examine it, but mention it in case somebody recognises
which scriptlet it comes from.