Branch: refs/heads/master
  Home:   https://github.com/tianocore/edk2
  Commit: 046ba401c29618e2065aad10db20f62a974f1439
      
https://github.com/tianocore/edk2/commit/046ba401c29618e2065aad10db20f62a974f1439
  Author: Tom Lendacky <thomas.lenda...@amd.com>
  Date:   2025-07-21 (Mon, 21 Jul 2025)

  Changed paths:
    M UefiCpuPkg/Library/MpInitLib/AmdSev.c
    M UefiCpuPkg/Library/MpInitLib/MpLib.c
    M UefiCpuPkg/Library/MpInitLib/X64/AmdSev.nasm

  Log Message:
  -----------
  UefiCpuPkg/MpInitLib: Fix random SEV-ES guest boot crash

The SevSnpKnownInitApicId field within the MP_CPU_EXCHANGE_INFO structure
is not guaranteed to be zero when booting an SEV-ES guest. While the check
in SevSnpGetInitCpuNumber() is conditionally guarded by verifying if the
guest is an SEV-SNP guest, the check in SevEsGetApicId() is not similarly
guarded.

This lack of protection can cause SevEsGetApicId() to return to the wrong
location. If the value of the SevSnpKnownInitApicId field contains the
exact random value of 1, the guest will be treated as an SEV-SNP guest
rather than an SEV-ES guest and return to the wrong location in the code
which will lead to a crash.

Ensure that all SEV related fields in MP_CPU_EXCHANGE_INFO structure are
properly initialized, thus removing the need for guarding access to the
SevSnpKnownInitApicId field.

Fixes: dca5d26bc57e ("UefiCpuPkg/MpInitLib: Fix SNP AP creation when using 
known APIC IDs")
Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com>


  Commit: 6f939cee32ab1fb78f7ff7e5179c02ab88ed9c49
      
https://github.com/tianocore/edk2/commit/6f939cee32ab1fb78f7ff7e5179c02ab88ed9c49
  Author: Tom Lendacky <thomas.lenda...@amd.com>
  Date:   2025-07-21 (Mon, 21 Jul 2025)

  Changed paths:
    M UefiCpuPkg/Library/MpInitLib/AmdSev.c
    M UefiCpuPkg/Library/MpInitLib/MpLib.c
    M UefiCpuPkg/Library/MpInitLib/MpLib.h

  Log Message:
  -----------
  UefiCpuPkg/MpInitLib: Rename FillExchangeInfoDataSevEs()

The FillExchangeInfoDataSevEs() is only called for SEV-SNP guests, but
the name (and comment in MpLib.c) implies that it is also called for
SEV-ES guests. Rename the function to FillExchangeInfoDataSevSnp() to
avoid confusion.

Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com>


Compare: https://github.com/tianocore/edk2/compare/0bb4cf0228fc...6f939cee32ab

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