A friend’s “early 2014” MacBookAir6,2 does not have issues with the old iso image. It seems likely that only old Macbooks are affected.
On Sun, Apr 21, 2019 at 02:27:10PM +0200, Thomas Schmitt wrote: > > I change it to > > 80 00 02 00 01 01 12 4f 01 00 00 00 3f 0b 00 00 > > I dd the changed mysdc2.img back to /dev/sdc2. > > > > Now it boots. :) > > […] > > Strangely, I now have only one entry “GRUB 2.02” in > > the boot selection, but “EFI Boot” (or what it was called) is gone. > > What do you see if the partition entry is zeroized entirely ? > I see both “GRUB 2.02” and “EFI Boot” when I zero it (I have not tried on Guix 0.16.0 this time though). So the options are: · Update mtools and then somehow patch mformat to zero out this region. · Patch grub-mkrescue instead to make it use mformat -k. Vladimir Serbinenko on the grub-devel list said this removes only information that is “Probably” not useful anyway, see https://lists.gnu.org/archive/html/grub-devel/2019-04/msg00100.html · Ignore the issue. The only affected machines we know are old Macbooks. Regards, Florian