Comment 3 for bug 1488632

It appears that we're failing due to this feature/bug in the use of partprobe on an empty (wiped) disk:

https://bugs.launchpad.net/ubuntu/+source/parted/+bug/1104797

note, blockdev --rereadpt fails as well (for likely the same reason, no pt table to read)

We can:

1) update devsync() 's subp call to partprobe to accept rcs=[0,1]
2) come up with some other mechanism to detect and skip partition probing on devices that don't have a partition table.
3) drop devsync use when running trusty (it's not systemd-udevd racy like vivid and newer).