Comment 12 for bug 107326

I'm pretty confident that the gptsync patch is still needed on Macs in order to make the firmware recognise it; the grub patch is necessary but not sufficient. Yes, it violates the standard, but that's Apple's fault ...

I think the suggestion in https://bugs.launchpad.net/ubuntu/+source/parted/+bug/107326/comments/5 to conditionalise it on <2TB disks is reasonable. Another option would be to conditionalise it on whether the running system is a Mac. There are advantages and disadvantages to both. Just checking the disk size is a heck of a lot easier than messing about with DMI to figure out the running system, and wouldn't break the ability to pull out a disk and fiddle with it on another system. However, I suspect pulling out disks from Macs and partitioning them on non-Macs is really pretty rare, and I'd rather our behaviour on non-Mac systems were consistent between 1.9TB and 2.1TB disks.