M4 users w/ EFI - possible solution

Kilobyte Kid

M4 users w/ EFI - possible solution

I've made an ISO with an updated syslinux 6.01 bootloader which now supports EFI


if you want grab syslinux here




I used cdrtfe 1.5 to make the iso




Anyone with an EFI system willing to try this?


ISO here



4 Replies
Kilobyte Kid

Re: M4 users w/ EFI - possible solution

infuscomus, I'm curious if you have EFI and if so, did it upgrade for you?

Dual Channel Surfer

Re: M4 users w/ EFI - possible solution

Thanks for creating this, but I'm not sure I understand... why an iso?

Isn't the main problem with people that have removed the DVD drive from their Macbook Pro or other apple computer and booting from the CD/DVD is not an option? Or are we looking at people with pc hardware that don't have a reliable legacy boot mode, in which case, aren't most of the problems booting from USB?


Most people can boot from CDROM, so I will attempt to boot from USB, in which case I should install the files to a bootable USB.

Will the EFI firmware allow booting from that folder \BOOT\ISOLINUX which isn't the EFI default?
In any case I will take some notes as I go....

If I try to reboot a Macbook Pro 13 inch late 2011, with a bootable USB and those files copied to \BOOT\ISOLINUX and I hold down the option key at boot, as suspected it doesn't show the USB as an EFI boot option, but the same USB will boot gparted-live when the grub EFI bootloader is in \EFI\boot

So now I'm trying to install to the USB under the default \EFI\BOOT

In which case I think we can rename syslinux.efi to bootia32.efi -  checking the file size, that's the one you've used.

But as expected, that doesn't work either - Macbook is 64 bit so we need the 64 bit version.

Now I can download the latest syslinux from here: https://www.kernel.org/pub/linux/utils/boot/syslinux/

Then I can pick the 64 bit version from syslinix 6.01 download: efi64/efi/syslinux.efi
Then copy to the USB:  \EFI\boot\bootx64.efi

Now now we finally have something that the Mac sees as a EFI bootable device.
But the boot fails. Smiley Sad

So again we are missing something, so from the syslinix 6.01 download: efi64/com32/elflink/
Then copy to the USB:  \EFI\boot\ldlinux.e64

Now boot the Mac again with the option key held while booting.
Select the "EFI boot" option...

Unfortunately this causes my Mac to lock up and I don't get any further. Smiley Sad

I take this to my linux pc with gigabyte Z77 UEFI motherboard and boot from the UEFI USB:
I get the message:

WARNING: No configuration file found


So we need to nename \EFI\boot\isolinux.cfg to \EFI\boot\syslinux.cfg
This gives the option of default or alternate.

The Mac still locks up, even with the renamed syslinux config file.

Back to the gigabyte UEFI... select the default option and we get:

Loading memdisk... ok
Loading boot2880.img...ok
bzImage version 0x203 unsupported
Booting kernel failed: no such file or directory


That's all I've got time for today, but the summary seems to be that if we use the right paths and the right files with the right names, we can EFI boot from the latest syslinux 6.0x - at least with some hardware and firmware combinations.


I suspect the bzImage version 0x203 unsupported problem might be the same old problem we have with grub-efi where the EFI system supports 32bit and 64bit and the FreeDOS image loaded by memdisk is 16bit. Having an EFI bootloader doesn't fix that problem.

Just to confirm the 64 bit EFI bootloader isn't broken, I was able to modify syslinux.cfg and boot the linux based gparted-live on the gigabyte UEFI from the same syslinux bootx64.efi.

Bit Baby

Re: M4 users w/ EFI - possible solution

Didn't boot in VMware Workstation 10 with an EFI VM.  I'm curious what it really did.

Kilobyte Kid

Re: M4 users w/ EFI - possible solution

Any word on this?