[Fedora-livecd-list] Mac (EFI) USB booting

[Stewart Adam]

On 1/19/09 1:19 PM, Jeremy Katz wrote:
> PowerMacs (PPC) are an entirely different beast and there's not really
> been any work done on getting them booting off of USB.
>
> For the x86 based Macs, it can work, but it's definitely far from just
> working everywhere right now.  The first question is if your machine is
> 32bit or 64bit EFI as we require matching x86 vs x86_64, respectively,
> based on that.  Most of the original Core Duo stuff is 32bit EFI, the
> newer is 64bit.  If you're using a 64bit EFI machine, right now, you're
> out of luck -- the kernel even in Fedora 10 was broken with 64bit EFI :(
I didn't think of giving it a on one of the older MacBook machines - I'll do 
that sometime soon. It could be a bug in the 64bit firmware, but I have 
tried using a i386 grub EFI image and i386 kernel on my early 2008 MacBook 
Po, but same symptoms as booting 64bit kernels.

> For 32bit, it _should_ work with Fedora 10.  But I don't think I've
> actually tested it on one of the Minis, and sadly, the Apple firmware
> has been notoriously bad about being buggy :)
Yup - the MBR USB bug seems to one of the more annoying ones :/

>> I gave up on EFI booting and even tried a classic MBR install with rEFIt but still the USB drive
>> is never detected. Is there another trick I'm missing here or does USB booting only work on a very
>> small subset of Intel Mac models? The recent EFI+MBR work looks interesting but like I said I can't
>> even get that far.
>
> I never managed to get rEFIt to boot off of an MBR-based USB device.
> Some people said they did, but I have no clue what they did to do so :)
There was so many reports with different results... If what I read was 
correct, it looks like some of Apple's older firmware didn't have the USB 
MBR booting bug, but the newer firmware (post BootCamp 2.0 I think) does. So 
really, anyone that runs Software Update or buys a Mac with the new BootCamp 
already installed doesn't have the ability to boot from USB drives with an 
MBR in rEFIt... Instead, rEFIt switches and uses the internal drive's MBR.

Stewart