diff --git a/OvmfPkg/Sec/Ia32/SecEntry.nasm b/OvmfPkg/Sec/Ia32/SecEntry.nasm
index 7fee1c2b2e..03501969eb 100644
--- a/OvmfPkg/Sec/Ia32/SecEntry.nasm
+++ b/OvmfPkg/Sec/Ia32/SecEntry.nasm
@@ -29,12 +29,30 @@ extern ASM_PFX(SecCoreStartupWithStack)
 ; @param[in]  EAX   Initial value of the EAX register (BIST: Built-in Self Test)
 ; @param[in]  DI    'BP': boot-strap processor, or 'AP': application processor
 ; @param[in]  EBP   Pointer to the start of the Boot Firmware Volume
+; @param[in]  DS    Selector allowing flat access to all addresses
+; @param[in]  ES    Selector allowing flat access to all addresses
+; @param[in]  FS    Selector allowing flat access to all addresses
+; @param[in]  GS    Selector allowing flat access to all addresses
+; @param[in]  SS    Selector allowing flat access to all addresses
 ;
 ; @return     None  This routine does not return
 ;
 global ASM_PFX(_ModuleEntryPoint)
 ASM_PFX(_ModuleEntryPoint):
 
+    ;
+    ; Fill the temporary RAM with the initial stack value.
+    ; The loop below will seed the heap as well, but that's harmless.
+    ;
+    mov     eax, FixedPcdGet32 (PcdInitValueInTempStack)      ; dword to store
+    mov     edi, FixedPcdGet32 (PcdOvmfSecPeiTempRamBase)     ; base address,
+                                                              ;   relative to
+                                                              ;   ES
+    mov     ecx, FixedPcdGet32 (PcdOvmfSecPeiTempRamSize) / 4 ; dword count
+    cld                                                       ; store from base
+                                                              ;   up
+    rep stosd
+
     ;
     ; Load temporary RAM stack based on PCDs
     ;
diff --git a/OvmfPkg/Sec/SecMain.inf b/OvmfPkg/Sec/SecMain.inf
index 711b595309..6051cb3c6c 100644
--- a/OvmfPkg/Sec/SecMain.inf
+++ b/OvmfPkg/Sec/SecMain.inf
@@ -71,6 +71,7 @@
   gEfiMdePkgTokenSpaceGuid.PcdGuidedExtractHandlerTableAddress
   gUefiOvmfPkgTokenSpaceGuid.PcdGuidedExtractHandlerTableSize
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDecompressionScratchEnd
+  gEfiMdeModulePkgTokenSpaceGuid.PcdInitValueInTempStack
 
 [FeaturePcd]
   gUefiOvmfPkgTokenSpaceGuid.PcdSmmSmramRequire