There has been some change between the 4.13 and 4.14-rc5 kernel. I am using the same userspace with those two kernels. 4.13 successfully reports the UUID using 'blkid /dev/sdX' for all cases.
However, when I switch to the 4.14-rc5 kernel, I can successfully query /dev/sda1 for the UUID. However, /dev/sda2 returns an error code of 2. Very strange that it works for one and not the other. I have ext3 filesystems using e2fsprogs-1.43.3 and util-linux-2.28.2. - Matthew Whitehead
