3 files changed, 12 insertions, 1 deletions
diff --git a/OvmfPkg/Include/Library/MemEncryptSevLib.h b/OvmfPkg/Include/Library/MemEncryptSevLib.h
index dc09c61e58..a2c70aa550 100644
--- a/OvmfPkg/Include/Library/MemEncryptSevLib.h
+++ b/OvmfPkg/Include/Library/MemEncryptSevLib.h
@@ -29,6 +29,8 @@ typedef struct _SEC_SEV_ES_WORK_AREA {
   UINT8    Reserved1[7];
 
   UINT64   RandomData;
+
+  UINT64   EncryptionMask;
 } SEC_SEV_ES_WORK_AREA;
 
 /**
diff --git a/OvmfPkg/ResetVector/Ia32/PageTables64.asm b/OvmfPkg/ResetVector/Ia32/PageTables64.asm
index a1771dfdec..5fae8986d9 100644
--- a/OvmfPkg/ResetVector/Ia32/PageTables64.asm
+++ b/OvmfPkg/ResetVector/Ia32/PageTables64.asm
@@ -145,7 +145,7 @@ GetSevEncBit:
 
     ; The encryption bit position is always above 31
     sub       ebx, 32
-    jns       SevExit
+    jns       SevSaveMask
 
     ; Encryption bit was reported as 31 or below, enter a HLT loop
 SevEncBitLowHlt:
@@ -153,6 +153,14 @@ SevEncBitLowHlt:
     hlt
     jmp       SevEncBitLowHlt
 
+SevSaveMask:
+    xor       edx, edx
+    bts       edx, ebx
+
+    mov       dword[SEV_ES_WORK_AREA_ENC_MASK], 0
+    mov       dword[SEV_ES_WORK_AREA_ENC_MASK + 4], edx
+    jmp       SevExit
+
 NoSev:
     ;
     ; Perform an SEV-ES sanity check by seeing if a #VC exception occurred.
diff --git a/OvmfPkg/ResetVector/ResetVector.nasmb b/OvmfPkg/ResetVector/ResetVector.nasmb
index d3aa879829..5fbacaed5f 100644
--- a/OvmfPkg/ResetVector/ResetVector.nasmb
+++ b/OvmfPkg/ResetVector/ResetVector.nasmb
@@ -74,6 +74,7 @@
   %define GHCB_SIZE (FixedPcdGet32 (PcdOvmfSecGhcbSize))
   %define SEV_ES_WORK_AREA (FixedPcdGet32 (PcdSevEsWorkAreaBase))
   %define SEV_ES_WORK_AREA_RDRAND (FixedPcdGet32 (PcdSevEsWorkAreaBase) + 8)
+  %define SEV_ES_WORK_AREA_ENC_MASK (FixedPcdGet32 (PcdSevEsWorkAreaBase) + 16)
   %define SEV_ES_VC_TOP_OF_STACK (FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) + FixedPcdGet32 (PcdOvmfSecPeiTempRamSize))
 %include "Ia32/Flat32ToFlat64.asm"
 %include "Ia32/PageTables64.asm"