[PATCH v2 0/2] OvmfPkg: Enable measured direct boot on AMD SEV-SNP

["Dov Murik" <dovmurik@linux.ibm.com>]

(Note: This is a new version of this one-year-old patch series; the v1
series [1] got a few Acked-by but it's been so long that I don't
consider them relevant anymore.)

AMD SEV and SEV-ES support measured direct boot with
kernel/initrd/cmdline hashes injected by QEMU and verified by OVMF
during boot.

To enable the same approach for AMD SEV-SNP we make sure the page in
which QEMU inserts the hashes of kernel/initrd/cmdline is not already
pre-validated, as SNP doesn't allow validating a page twice.

The first patch rearranges the pages in AmdSevX64's MEMFD so they are in
the same order both as in the main target (OvmfPkgX64), with the
exception of the SEV Launch Secret page which isn't defined in
OvmfPkgX64.

The second patch modifies the SNP metadata structure such that on
AmdSev target the SEV Launch Secret page is not included in the ranges
that are pre-validated (zero pages) by the VMM; instead the VMM will
insert content into this page (the hashes table), or mark it explicitly
as a zero page if no hashes are added.

A corresponding RFC patch to QEMU will be published soon in qemu-devel.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: Ashish Kalra <ashish.kalra@amd.com>
Cc: Mario Smarduch <mario.smarduch@amd.com>
Cc: Tobin Feldman-Fitzthum <tobin@linux.ibm.com>

---

v2 changes:
* Rebased on master
* Updated AmdSev MEMFD size to match OvmfX64

v1:
[1] https://edk2.groups.io/g/devel/message/88137


Dov Murik (2):
  OvmfPkg/AmdSev: Reorder MEMFD pages to match the order in
    OvmfPkgX64.fdf
  OvmfPkg/ResetVector: Exclude SEV launch secrets page from
    pre-validation

 OvmfPkg/AmdSev/AmdSevX64.fdf          | 27 ++++++++++----------
 OvmfPkg/ResetVector/ResetVector.nasmb | 14 +++++++++-
 2 files changed, 27 insertions(+), 14 deletions(-)

-- 
2.25.1