Linux 3.15 Kernel Gains EFI Mixed Mode Support

[phoronix]

Phoronix: Linux 3.15 Kernel Gains EFI Mixed Mode Support

Landing into the latest Linux kernel code for version 3.15 is EFI mixed mode support that will allow 64-bit kernels to run from 32-bit EFI firmware...

http://www.phoronix.com/vr.php?view=MTY0OTI

[GreatEmerald]

Huh, so they decided to support this after all...

[LLStarks]

There are too many stupid OEMs who are shoving 32-bit UEFI into their x86 tablets because they figure users will never notice or need anything other than Windows.

[garegin]

about time. I still don't understand why we have 32 bit uefi to begin with, but whatever.

[BSDude]

about time. I still don't understand why we have 32 bit uefi to begin with, but whatever.

Mhmmmm! I was thinking the same thing. Wasn't uEFI made for new hardware in a time when 64bit was commonplace and/or at least on 80% of desktop/laptop PCs?

[GreatEmerald]

Mhmmmm! I was thinking the same thing. Wasn't uEFI made for new hardware in a time when 64bit was commonplace and/or at least on 80% of desktop/laptop PCs?

I think Matthew Garrett had an explanation somewhere. Something like that OEMs only thought about 32-bit Windows, but wanted to have both UEFI and x86_64 CPUs, and thus the weird situation.

[FLHerne]

Curse them! I spend two days grappling with this stuff, and then they announce proper support for it!?

Ah well, definitely useful. Thanks, devs!

[erendorn]

Mhmmmm! I was thinking the same thing. Wasn't uEFI made for new hardware in a time when 64bit was commonplace and/or at least on 80% of desktop/laptop PCs?

The bay trail boards happen to have some hardware for which the 64 bits windows driver crashes while the 32 bit one does not.
Given that these devices have less than 4Gb ram, they decided it was just as good to ship some 32 bit versions now and fix the driver for later versions.

[jaxxed]

EFI & BTRFS subvolume roots yet?

Slightly off-topic, but does anyone know if we can do direct EFI boot-loading (efibootmgr) with root partitions stored on BTRFS disks with a root subvolume?

[Yaro]

Phoronix: Linux 3.15 Kernel Gains EFI Mixed Mode Support

Landing into the latest Linux kernel code for version 3.15 is EFI mixed mode support that will allow 64-bit kernels to run from 32-bit EFI firmware...

What an underwhelming new feature. How many actual real-world 32-bit (U)EFI implementations actually exist out there on devices/machines that can even have Linux installed on them?