Re: [edk2-devel] [PATCH v3 0/3] SEV Page Encryption Bitmap support for OVMF.

["Ashish Kalra" <ashish.kalra@amd.com>]

On Fri, Dec 04, 2020 at 04:50:05AM +0100, Laszlo Ersek wrote:
> On 12/04/20 01:03, Ashish Kalra wrote:
> > From: Ashish Kalra <ashish.kalra@amd.com>
> > 
> > By default all the SEV guest memory regions are considered encrypted,
> > if a guest changes the encryption attribute of the page (e.g mark a
> > page as decrypted) then notify hypervisor. Hypervisor will need to
> > track the unencrypted pages. The information will be used during
> > guest live migration, guest page migration and guest debugging.
> > 
> > The patch-set also adds a new SEV and SEV-ES hypercall abstraction
> > library to support SEV Page encryption/decryption status hypercalls
> > for SEV and SEV-ES guests.
> > 
> > BaseMemEncryptSevLib invokes hypercalls via this new hypercall library.
> > 
> > A branch containing these patches is available here:
> > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fashkalra%2Fedk2%2Ftree%2Fsev_page_encryption_bitmap_v3&amp;data=04%7C01%7Cashish.kalra%40amd.com%7Cbc3c88f21f1d40b322b408d89807b5c8%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637426506192800828%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=VZzP2MVJSECgMhOyuCCASw58g74BiCVAH9JW8hZG3Tw%3D&amp;reserved=0
> > 
> > Changes since v2:
> >  - GHCB_BASE setup during reset-vector as decrypted is marked explicitly
> >    in the hypervisor page encryption bitmap after setting the 
> >    PcdSevEsIsEnabled PCD.
> > 
> > Changes since v1:
> >  - Mark GHCB_BASE setup during reset-vector as decrypted explicitly in
> >    the hypervisor page encryption bitmap.
> >  - Resending the series with correct shallow threading.
> > 
> > Ashish Kalra (2):
> >   OvmfPkg/MemEncryptHypercallLib: add library to support SEV hypercalls.
> >   OvmfPkg/PlatformPei: Mark SEC GHCB page in the page encrpytion bitmap.
> > 
> > Brijesh Singh (1):
> >   OvmfPkg/BaseMemEncryptLib: Support to issue unencrypted hypercall
> > 
> >  .../Include/Library/MemEncryptHypercallLib.h  |  37 ++++++
> >  .../BaseMemEncryptSevLib.inf                  |   1 +
> >  .../BaseMemEncryptSevLib/X64/VirtualMemory.c  |  18 +++
> >  .../MemEncryptHypercallLib.c                  | 105 ++++++++++++++++++
> >  .../MemEncryptHypercallLib.inf                |  39 +++++++
> >  .../X64/AsmHelperStub.nasm                    |  39 +++++++
> >  OvmfPkg/OvmfPkgX64.dsc                        |   1 +
> >  OvmfPkg/PlatformPei/AmdSev.c                  |  10 ++
> >  8 files changed, 250 insertions(+)
> >  create mode 100644 OvmfPkg/Include/Library/MemEncryptHypercallLib.h
> >  create mode 100644 OvmfPkg/Library/MemEncryptHypercallLib/MemEncryptHypercallLib.c
> >  create mode 100644 OvmfPkg/Library/MemEncryptHypercallLib/MemEncryptHypercallLib.inf
> >  create mode 100644 OvmfPkg/Library/MemEncryptHypercallLib/X64/AsmHelperStub.nasm
> > 
> 
> I'll need some time to get to this series.
> 
> I'm fairly certain though, from a quick skim, that this series breaks
> all DSC files under OvmfPkg except X64. Please fix that.
> 
> 

Ok thanks Laszlo, i will fix this.

Ashish