Noticed this error while using 16.04-server today. The system boots fine. (save for a very long time-out waiting for a network that has an active link, but I digress) But shortly thereafter (a minute or so) this error starts appearing.
These two topics address the issue from the perspective of either an errant BIOS setting or the practice of some VM software defaulting to reporting a floppy is available when it isn't:
blk_update_request: I/O error, dev fd0, sector 0
"Buffer I/O error on device fd0, logical block 0" error
However in my case, I really do have a floppy drive. Is the only solution to disable it? Is there not an actual cause of the error to solve?
Note, /etc/fstab looks fine as far as I can tell. The UUIDs are correct for both / and swap. The /dev/fd0 is mounted as /media/floppy0 presumably because there isn't an actual floppy in the drive.