Comment # 6 on bug 934640 from Stefan Hundhammer

Now setting disks to "read only" when probing with "parted" reports an I/O
error.

Notice that the expert partitioner might still not prevent users from trying to
create a new disk label (ms-dos or GPT) on that device.

Also notice that real I/O errors might now be shadowed by this since we cannot
reasonably distinguish them from this scenario here.