Re: [PATCHv2, RFC] x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G

[Kirill A. Shutemov]

On Sat, Oct 14, 2017 at 09:33:53AM +0200, Ingo Molnar wrote:
> Yeah, so first most of this code should be moved from assembly to C. Any reason 
> why that cannot be done?

Well, we can move a little bit more code into C, like populating the
trampoline page, but I don't the think we can move the rest.

Switching to compatibility mode is too low-level to be written in C.

And we cannot write the trampoline code in C, as it's in 32-bit mode and
we wouldn't be able to generate it from C in a sane manner while building
64-bit kernel (we discussed this before).

-- 
 Kirill A. Shutemov