OK I've got this working. The problem was user error. Explicitly setting root is necessary, and I've updated the bug. https://savannah.gnu.org/bugs/index.php?42954
So the approach of chainloading Apple's boot.efi is valid. What's needed is to consider Recovery HD (Apple Boot partitiontype GUID) to be the partition searched by os-prober, figure out its UUID so that set root can be done by UUID. The Apple Boot [1] is used by OS X 10.7 through 10.10, so it's a good start point to search for OS X since it won't be anywhere else. Going forward, any conventional HFS+ partition [2] isn't going to be OS X, but instead will be any distribution using mactel boot, since putting grubx64.efi on the FAT32 ESP is *not* picked up by Apple's firmware as a legit bootloader. Only if there is an NVRAM entry for it, and bootcurrent has it listed first, can it be used. By putting grubx64.efi on hfsplus, and tricking the firmware into thinking it's an OS X bootloader, we get a prettier user friendly linux boot experience on Macs. [1] partitiontype GUID 426F6F74-0000-11AA-AA11-00306543ECAC [2] partitiontype GUID 48465300-0000-11AA-AA11-00306543ECAC Chris Murphy _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
