OvmfPkg/RiscVVirt: Add Stack HOB

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4350

Currently, stack HOB is not created for the stack memory. This causes
stack memory to be treated as free memory and any memory allocation which
happens at this address causes random memory corruption. Fix this by
creating the stack HOB which marks the memory as BS data.

Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Andrei Warkentin <andrei.warkentin@intel.com>
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>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reported-by: Andrei Warkentin <andrei.warkentin@intel.com>
Tested-by: Andrei Warkentin <andrei.warkentin@intel.com>
Reviewed-by: Andrei Warkentin <andrei.warkentin@intel.com>

OvmfPkg/RiscVVirt/Sec/SecMain.c

@@ -55,6 +55,7 @@ SecStartup (
   EFI_STATUS                  Status;
   UINT64                      UefiMemoryBase;
   UINT64                      StackBase;
+  UINT32                      StackSize;
 
   //
   // Report Status Code to indicate entering SEC core
@@ -71,9 +72,9 @@ SecStartup (
   FirmwareContext.FlattenedDeviceTree = (UINT64)DeviceTreeAddress;
   SetFirmwareContextPointer (&FirmwareContext);
 
-  StackBase = (UINT64)FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) +
-              FixedPcdGet32 (PcdOvmfSecPeiTempRamSize);
-  UefiMemoryBase = StackBase - SIZE_32MB;
+  StackBase      = (UINT64)FixedPcdGet32 (PcdOvmfSecPeiTempRamBase);
+  StackSize      = FixedPcdGet32 (PcdOvmfSecPeiTempRamSize);
+  UefiMemoryBase = StackBase + StackSize - SIZE_32MB;
 
   // Declare the PI/UEFI memory region
   HobList = HobConstructor (
@@ -86,6 +87,8 @@ SecStartup (
 
   SecInitializePlatform ();
 
+  BuildStackHob (StackBase, StackSize);
+
   //
   // Process all libraries constructor function linked to SecMain.
   //