Bottomley: Owning your Windows 8 UEFI Platform [LWN.net]

Bottomley: Owning your Windows 8 UEFI Platform

Posted Feb 25, 2013 20:42 UTC (Mon) by khim (subscriber, #9252)
In reply to: Bottomley: Owning your Windows 8 UEFI Platform by nix
Parent article: Bottomley: Owning your Windows 8 UEFI Platform

EFI-supporting BIOSes can also boot in BIOS mode for backward compatibility

"EFI-supporting BIOS" is an oxymoron. Most such BIOSes are, in fact, thin BIOS emulation shims on top of the real thing: EFI-based firmware.

and (obviously) still boot the Management Engine long before they make the decision to do that

Yup. They start as EFI and then pretend they are BIOS. This combines worst sides of EFI and BIOS approaches but makes older OSes happy if you are lucky. It still means that without EFI your hardware will not boot.

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Bottomley: Owning your Windows 8 UEFI Platform

Posted Feb 26, 2013 15:38 UTC (Tue) by nix (subscriber, #2304) [Link]

That entirely depends on what you mean by 'without EFI'. From my POV, in BIOS mode, my motherboard's EFI is just an implementation detail used by very early boot, of no interest once software I can control is running: among other things, I don't need an EFI partition, an EFI bootloader, or any of the other EFI PE stuff. It might as well be an old-style BIOS from my perspective. (The sensors don't work, but that's got nothing to do with EFI and everything to do with a sensor vendor and motherboard vendor who refuse to release any information on the sensor chip: each refers you to the other for info and neither will give you any).