ASUS T100 with 64-bit Ubuntu

Colin Watson cjwatson at
Wed Nov 19 09:04:55 UTC 2014

On Tue, Nov 11, 2014 at 12:55:34PM +0000, Matt Fleming wrote:
> Has anyone looked into enabling CONFIG_EFI_MIXED for 64-bit kernels?

This is already enabled in our current kernels.  (And thanks for adding
this option!)

> This kernel config option allows CPUs that support 64-bit long mode but
> ship with a 32-bit UEFI firmware (such as the ASUS T100) to run a 64-bit
> kernel, with the necessary thunking taken care of whenever firmware
> calls are required.
> To get this working out of the box, it'd be necessary to ship a 32-bit
> EFI boot loader as part of the 64-bit installation media. Apart from
> that, once the kernel is booted, the existing 64-bit userspace should
> work fine.

I posted a list of what I think we need to do here:

Colin Watson                                       [cjwatson at]

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