Description of problem: Running Fedora 27 x86_64 on Macbook Pro with 2 disks, Linux EFI boot and root partitions in 2nd disk, OSX partition in first disk. grub2-mkconfig generates partition root references based on enumeration of disks starting with 0 (e.g. hd0, hd1, etc.) but grub2 using efi gpt (possibly installed from anaconda) uses the partition reference with disk number from 1 (hd1,gpt1, hd1,gpt2, etc.) Version-Release number of selected component (if applicable): grub2-tools-efi-2.02-22.fc27.x86_64 grub2-tools-2.02-22.fc27.x86_64 anaconda and grub2 from stock installer How reproducible: Always Steps to Reproduce: 1. run grub2-mkconfig -o /boot/efi/EFI/fedora/grub2.cfg 2. systemctl reboot 3. in grub2 menu, choose Mac OSX entry that contains 'set root=hd0,gpt3', press Enter Actual results: error: disk 'hd0,gpt3' not found error: you need to load the kernel first Expected results: Boot OSX normally Additional info: At the grub menu, press 'c' to enter grub command line, and type 'ls'. It lists the following: (hd0) (hd1) (hd1,gpt3) (hd1,gpt2) (hd1,gpt1) (hd2) (hd2,gpt8) (hd2,gpt7) ... This shows 3 disks, hd0, hd1, hd2, even though there is no 3rd disk, and no partition is listed for hd0. All partitions show hd1 as first disk and hd2 as second disk. The Linux that is in the second disk (hd1,gpt6) boots fine, but OSX that is in first disk (hd0,gpt3) does not. When I modify to boot (hd1,gpt3), it does boot OSX fine! So somehow grub2 boot image installed from anaconda is confusing (hd1,gpt3) as first disk partition 3 rather than second disk partition 3, or somehow hd0 is skipped as no partition.
Upon checking other bugs, I find that bug#1524685 is basically the same, with more detail than what I reported. I am self-closing this bug as duplicate. *** This bug has been marked as a duplicate of bug 1524685 ***