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Re: meeting planning



John Paul Adrian Glaubitz dixit:

>> The partitioning scheme is independent of the firmware in use.
>
>Not quite. You won't be able to boot from anything of that unless your
>firmware supports that.

Only somewhat right. You have to honour the boot protocol supported
by the firmware, but that is not often coupled to the partitioning
scheme.

>If you want to use GPT and be able to boot from that, you need UEFI.
[…]
>No, you can't boot from a GPT partition with a classical BIOS. How is
>a non-UEFI firmware supposed to know anything about GPT partition
>tables?

This is totally and utterly wrong.

The PC BIOS boot protocol is:

“Read the first 512-octet sector into RAM at 07C00h, then jump to
that address. Keep the drive number we booted from (00h = floppy,
80h = hard disc; others usually unsupported) in the DL register.”

It *is* true that an EFI firmware cannot normally boot from a
hard disc with a Sun disklabel. Funnily enough, a PC BIOS *can*
as long as you put i386 machine code into it to the right places.

/MirOS/current/cdrom10.iso is an example for this; the image is
partitioned with a Sun disklabel (in sector 0) and El Torito.

I’ve written PC bootloaders and bootmanagers since I was about
eleven years old.

bye,
//mirabilos
-- 
> emacs als auch vi zum Kotzen finde (joe rules) und pine für den einzig
> bedienbaren textmode-mailclient halte (und ich hab sie alle ausprobiert). ;)
Hallooooo, ich bin der Holger ("Hallo Holger!"), und ich bin ebenfalls
... pine-User, und das auch noch gewohnheitsmäßig ("Oooooooohhh").  [aus dasr]


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