Broken UEFI implementations: Difference between revisions

CDs can be booted through the option key menu if they're set up properly. There are also some caveats.

 

# This also means to make a disc that works on EFI+Apple+BIOS as both an ISO image /and/ an image on a USB stick, you need to actually /execute/ the APM header signature on BIOS machines. Thankfully that's pretty safe, but it's a little squicky in your head. [http://www.syslinux.org/wiki/index.php/The_Syslinux_Project syslinux]]'s "isohybrid" utility has had this ability to build this sort of image since version 4.05 .

# On some machines, there needs to be a special El Torito image for an HFS+ formatted ESP that conforms to what's above in [http://wiki.osdev.org/index.php?title=Broken_UEFI_implementations#There.27s_additional_UI_presented_mixed_in_with_BDS There's additional UI presented mixed in with BDS] in order to have it show your UEFI-bootable image as anything other than "Windows". This means there are /three/ El Torito entries - the "Validation Entry" of type 0x00 (80x86), which holds the BIOS code, and then *two* entries of type 0xef - the HFS+ and then the FAT one. The HFS+ one needs to be last one. Tools like mkisofs can make ISOs with multiple images with the several boot images using the "-eltorito-alt-boot" and "-e" options. There's some examples [https://fedoraproject.org/wiki/User:Pjones/BootableCDsForBIOSAndUEFI here].