On a MacPro 3,1 with a stock installation of Ubuntu 16.10 amd64 from ubuntu-16.10-desktop-amd64.iso , the mounted volumes on the Dock of the Desktop are incorrect. The machine has three SATA drives installed. Two of these are formatted as RAID-1 slices of an AppleRAID Journaled HFS volume. Those two slices appear as separate hard drive icons in the Dock (both being labelled 'Macintosh HD') which is the correct AppleRAID volume name. However these two hard drive icons (both labelled 'Macintosh HD') are unresponsive to clicks. The third SATA drive, a normal Journaled HFS volume 'El Capitan HD' is mounted as expected in at "/media/howarth/El Capitan HD". Neither the AppleRAID slices nor the AppleRAID volume itself appears in /media/howarth as a mounted volume.
I wonder how much of this problem is related to EFI support. The option boot selector on Intel Macs displays each of the AppleRAID slices as individual bootable volumes (eg 'Macintosh HD' and 'Macintosh HD 1'). Perhaps the two dead hard drive icons in the Unity desktop Dock are a side effect of that behavior in EFI (which doesn''t show the combined AppleRAID volume in the boot selector).
Not sure I see the connection with Openmp