[edk2-devel] [PATCH V5 2/2] OvmfPkg/ResetVector: Enable Intel TDX in ResetVector of Ovmf

[Gerd Hoffmann]

  Hi,

> > Sure.  And I think we should add proper 5-level paging support to the current
> > ovmf implementation instead of adding hacks to the tdx code.
> My understanding is that we should first add 5-level paging support in OVMF, right?

Well, the page table setup should be in common code not tdx code as
5-level paging isn't something tdx-specific.

I'd suggest to add this to OvmfPkg/ResetVector/Ia32/PageTables64.asm.
Reserve one more page, setup the tables for 5-level paging by inserting
a level 5 page directory.

When using 5-level paging let cr3 point to the first page (level 5
pagedir), when using 4-level paging let cr3 point to the second page
(level 4 pagedir).

Can be part of this patch series, just make it a separate patch for
easier review.

Whenever we should enable 5-level paging even in non-tdx mode or use
5-level paging only with tdx is a separate question.  We can continue to
use 4-level paging in non-tdx mode for now and discuss that later.

I'm not sure which implications this would have for booting older
kernels, when handing over control to a OS kernel without 5-level paging
support but 5-level paging enabled (non-issue for tdx as this requires a
new tdx-aware guest kernel anyway ...).

take care,
  Gerd



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#80147): https://edk2.groups.io/g/devel/message/80147
Mute This Topic: https://groups.io/mt/85242569/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-