diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
index 714b5d8..2918d58 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWrite.c
@@ -39,7 +39,10 @@ FtwGetMaxBlockSize (
 {
   EFI_FTW_DEVICE  *FtwDevice;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   if (!FeaturePcdGet(PcdFullFtwServiceEnable)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_UNSUPPORTED;
   }
 
@@ -47,6 +50,8 @@ FtwGetMaxBlockSize (
 
   *BlockSize  = FtwDevice->SpareAreaLength;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2, BlockSize=0x%Lx\n", __FUNCTION__,
+    (UINT64) *BlockSize));
   return EFI_SUCCESS;
 }
 
@@ -86,10 +91,15 @@ FtwAllocate (
   EFI_FTW_DEVICE                  *FtwDevice;
   EFI_FAULT_TOLERANT_WRITE_HEADER *FtwHeader;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, CallerId=%g, PrivateDataSize=0x%Lx, "
+    "NumberOfWrites=0x%Lx\n", __FUNCTION__, CallerId, (UINT64)PrivateDataSize,
+    (UINT64)NumberOfWrites));
+
   FtwDevice = FTW_CONTEXT_FROM_THIS (This);
 
   Status    = WorkSpaceRefresh (FtwDevice);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -97,6 +107,7 @@ FtwAllocate (
   //
   if (FTW_WRITE_TOTAL_SIZE (NumberOfWrites, PrivateDataSize) > FtwDevice->FtwWorkSpaceHeader->WriteQueueSize) {
     DEBUG ((EFI_D_ERROR, "Ftw: Allocate() request exceed Workspace, Caller: %g\n", CallerId));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
     return EFI_BUFFER_TOO_SMALL;
   }
   //
@@ -109,6 +120,7 @@ FtwAllocate (
   // Previous write has not completed, access denied.
   //
   if ((FtwHeader->HeaderAllocated == FTW_VALID_STATE) || (FtwHeader->WritesAllocated == FTW_VALID_STATE)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
     return EFI_ACCESS_DENIED;
   }
   //
@@ -118,6 +130,7 @@ FtwAllocate (
   if (Offset + FTW_WRITE_TOTAL_SIZE (NumberOfWrites, PrivateDataSize) > FtwDevice->FtwWorkSpaceSize) {
     Status = FtwReclaimWorkSpace (FtwDevice, TRUE);
     if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -143,6 +156,7 @@ FtwAllocate (
                                     (UINT8 *) FtwHeader
                                     );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 5: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -155,6 +169,7 @@ FtwAllocate (
             WRITES_ALLOCATED
             );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 6: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -165,6 +180,7 @@ FtwAllocate (
     NumberOfWrites)
     );
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 7\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -195,6 +211,8 @@ FtwWriteRecord (
   UINTN                           Offset;
   EFI_LBA                         WorkSpaceLbaOffset;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+ 
   FtwDevice = FTW_CONTEXT_FROM_THIS (This);
 
   WorkSpaceLbaOffset = FtwDevice->FtwWorkSpaceLba - FtwDevice->FtwWorkBlockLba;
@@ -223,6 +241,7 @@ FtwWriteRecord (
               SPARE_COMPLETED
               );
     if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -240,6 +259,7 @@ FtwWriteRecord (
   }
 
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -253,6 +273,7 @@ FtwWriteRecord (
             DEST_COMPLETED
             );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -272,10 +293,12 @@ FtwWriteRecord (
               );
     Header->Complete = FTW_VALID_STATE;
     if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 5\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -331,10 +354,15 @@ FtwWrite (
   UINT8                               *Ptr;
   EFI_PHYSICAL_ADDRESS                FvbPhysicalAddress;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx Length=0x%Lx "
+    "PrivateData=%p FvBlockHandle=%p Buffer=%p\n", __FUNCTION__, (UINT64)Lba,
+    (UINT64)Offset, (UINT64)Length, PrivateData, FvBlockHandle, Buffer));
+
   FtwDevice = FTW_CONTEXT_FROM_THIS (This);
 
   Status    = WorkSpaceRefresh (FtwDevice);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -349,6 +377,7 @@ FtwWrite (
       //
       Status = FtwAllocate (This, &gEfiCallerIdGuid, 0, 1);
       if (EFI_ERROR (Status)) {
+        DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
         return Status;
       }
     } else {
@@ -358,6 +387,7 @@ FtwWrite (
       //
       DEBUG ((EFI_D_ERROR, "Ftw: no allocates space for write record!\n"));
       DEBUG ((EFI_D_ERROR, "Ftw: Allocate service should be called before Write service!\n"));
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
       return EFI_NOT_READY;
     }
   }
@@ -366,6 +396,7 @@ FtwWrite (
   // If Record is out of the range of Header, return access denied.
   //
   if (((UINTN)((UINT8 *) Record - (UINT8 *) Header)) > FTW_WRITE_TOTAL_SIZE (Header->NumberOfWrites - 1, Header->PrivateDataSize)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4\n", __FUNCTION__));
     return EFI_ACCESS_DENIED;
   }
 
@@ -373,20 +404,24 @@ FtwWrite (
   // Check the COMPLETE flag of last write header
   //
   if (Header->Complete == FTW_VALID_STATE) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 5\n", __FUNCTION__));
     return EFI_ACCESS_DENIED;
   }
 
   if (Record->DestinationComplete == FTW_VALID_STATE) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 6\n", __FUNCTION__));
     return EFI_ACCESS_DENIED;
   }
 
   if ((Record->SpareComplete == FTW_VALID_STATE) && (Record->DestinationComplete != FTW_VALID_STATE)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 7\n", __FUNCTION__));
     return EFI_NOT_READY;
   }
   //
   // Check if the input data can fit within the target block
   //
   if ((Offset + Length) > FtwDevice->SpareAreaLength) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 8\n", __FUNCTION__));
     return EFI_BAD_BUFFER_SIZE;
   }
   //
@@ -394,12 +429,14 @@ FtwWrite (
   //
   Status = FtwGetFvbByHandle (FvBlockHandle, &Fvb);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 9: %r\n", __FUNCTION__, Status));
     return EFI_NOT_FOUND;
   }
 
   Status = Fvb->GetPhysicalAddress (Fvb, &FvbPhysicalAddress);
   if (EFI_ERROR (Status)) {
     DEBUG ((EFI_D_ERROR, "FtwLite: Get FVB physical address - %r\n", Status));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 10: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -431,6 +468,7 @@ FtwWrite (
                                     (UINT8 *) Record
                                     );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 11: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -442,6 +480,7 @@ FtwWrite (
   MyBufferSize  = FtwDevice->SpareAreaLength;
   MyBuffer      = AllocatePool (MyBufferSize);
   if (MyBuffer == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 12\n", __FUNCTION__));
     return EFI_OUT_OF_RESOURCES;
   }
   //
@@ -453,6 +492,7 @@ FtwWrite (
     Status    = Fvb->Read (Fvb, Lba + Index, 0, &MyLength, Ptr);
     if (EFI_ERROR (Status)) {
       FreePool (MyBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 13: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -472,6 +512,7 @@ FtwWrite (
   SpareBuffer     = AllocatePool (SpareBufferSize);
   if (SpareBuffer == NULL) {
     FreePool (MyBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 14\n", __FUNCTION__));
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -488,6 +529,7 @@ FtwWrite (
     if (EFI_ERROR (Status)) {
       FreePool (MyBuffer);
       FreePool (SpareBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 15: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -510,6 +552,7 @@ FtwWrite (
     if (EFI_ERROR (Status)) {
       FreePool (MyBuffer);
       FreePool (SpareBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 16: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -532,6 +575,7 @@ FtwWrite (
             );
   if (EFI_ERROR (Status)) {
     FreePool (SpareBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 17: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -544,6 +588,7 @@ FtwWrite (
   Status = FtwWriteRecord (This, Fvb);
   if (EFI_ERROR (Status)) {
     FreePool (SpareBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 18: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -562,6 +607,7 @@ FtwWrite (
                                         );
     if (EFI_ERROR (Status)) {
       FreePool (SpareBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 19: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -580,6 +626,7 @@ FtwWrite (
     Length)
     );
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 20\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -610,10 +657,14 @@ FtwRestart (
   EFI_FAULT_TOLERANT_WRITE_RECORD     *Record;
   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *Fvb;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, FvBlockHandle=%p\n", __FUNCTION__,
+    FvBlockHandle));
+
   FtwDevice = FTW_CONTEXT_FROM_THIS (This);
 
   Status    = WorkSpaceRefresh (FtwDevice);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -626,6 +677,7 @@ FtwRestart (
   //
   Status = FtwGetFvbByHandle (FvBlockHandle, &Fvb);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
     return EFI_NOT_FOUND;
   }
 
@@ -633,6 +685,7 @@ FtwRestart (
   // Check the COMPLETE flag of last write header
   //
   if (Header->Complete == FTW_VALID_STATE) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
     return EFI_ACCESS_DENIED;
   }
 
@@ -640,10 +693,12 @@ FtwRestart (
   // Check the flags of last write record
   //
   if (Record->DestinationComplete == FTW_VALID_STATE) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4\n", __FUNCTION__));
     return EFI_ACCESS_DENIED;
   }
 
   if ((Record->SpareComplete != FTW_VALID_STATE)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 5\n", __FUNCTION__));
     return EFI_ABORTED;
   }
 
@@ -653,6 +708,7 @@ FtwRestart (
   //
   Status = FtwWriteRecord (This, Fvb);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 6: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -663,6 +719,7 @@ FtwRestart (
   FtwEraseSpareBlock (FtwDevice);
 
   DEBUG ((EFI_D_ERROR, "Ftw: Restart() success \n"));
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 7\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -686,18 +743,23 @@ FtwAbort (
   UINTN           Offset;
   EFI_FTW_DEVICE  *FtwDevice;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   FtwDevice = FTW_CONTEXT_FROM_THIS (This);
 
   Status    = WorkSpaceRefresh (FtwDevice);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
   if (FtwDevice->FtwLastWriteHeader->HeaderAllocated != FTW_VALID_STATE) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
     return EFI_NOT_FOUND;
   }
 
   if (FtwDevice->FtwLastWriteHeader->Complete == FTW_VALID_STATE) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
     return EFI_NOT_FOUND;
   }
   //
@@ -711,12 +773,14 @@ FtwAbort (
             WRITES_COMPLETED
             );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
   FtwDevice->FtwLastWriteHeader->Complete = FTW_VALID_STATE;
 
   DEBUG ((EFI_D_ERROR, "Ftw: Abort() success \n"));
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 5\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -761,7 +825,11 @@ FtwGetLastWrite (
   EFI_FAULT_TOLERANT_WRITE_HEADER *Header;
   EFI_FAULT_TOLERANT_WRITE_RECORD *Record;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, PrivateDataSize=0x%Lx\n", __FUNCTION__,
+    (UINT64)*PrivateDataSize));
+
   if (!FeaturePcdGet(PcdFullFtwServiceEnable)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_UNSUPPORTED;
   }
 
@@ -769,6 +837,7 @@ FtwGetLastWrite (
 
   Status    = WorkSpaceRefresh (FtwDevice);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -786,6 +855,7 @@ FtwGetLastWrite (
 
     Status    = FtwAbort (This);
     *Complete = TRUE;
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
     return EFI_NOT_FOUND;
   }
   //
@@ -793,6 +863,7 @@ FtwGetLastWrite (
   //
   if (Header->HeaderAllocated != FTW_VALID_STATE) {
     *Complete = TRUE;
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4\n", __FUNCTION__));
     return EFI_NOT_FOUND;
   }
   //
@@ -803,6 +874,7 @@ FtwGetLastWrite (
     if (EFI_ERROR (Status)) {
       FtwAbort (This);
       *Complete = TRUE;
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 5: %r\n", __FUNCTION__, Status));
       return EFI_NOT_FOUND;
     }
     ASSERT (Record != NULL);
@@ -829,6 +901,11 @@ FtwGetLastWrite (
 
   DEBUG ((EFI_D_ERROR, "Ftw: GetLasetWrite() success\n"));
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 6, CallerId=%g Lba=0x%Lx Offset=0x%Lx "
+    "Length=0x%Lx PrivateDataSize=0x%Lx PrivateData=%p Complete=%d\n",
+    __FUNCTION__, CallerId, (UINT64)*Lba, (UINT64)*Offset, (UINT64)*Length,
+    (UINT64)*PrivateDataSize, PrivateData, *Complete));
+
   return Status;
 }
 
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c
index 1235bd8..caece56 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c
@@ -73,14 +73,19 @@ FtwGetFvbByHandle (
   OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  **FvBlock
   )
 {
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   //
   // To get the FVB protocol interface on the handle
   //
-  return gBS->HandleProtocol (
+  Status = gBS->HandleProtocol (
                 FvBlockHandle,
                 &gEfiFirmwareVolumeBlockProtocolGuid,
                 (VOID **) FvBlock
                 );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %r\n", __FUNCTION__, Status));
+  return Status;
 }
 
 /**
@@ -100,6 +105,7 @@ FtwGetSarProtocol (
 {
   EFI_STATUS                              Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   //
   // Locate Swap Address Range protocol
   //
@@ -108,6 +114,7 @@ FtwGetSarProtocol (
                   NULL, 
                   SarProtocol
                   );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %r\n", __FUNCTION__, Status));
   return Status;
 }
 
@@ -134,6 +141,7 @@ GetFvbCountAndBuffer (
 {
   EFI_STATUS                              Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   //
   // Locate all handles of Fvb protocol
   //
@@ -144,6 +152,7 @@ GetFvbCountAndBuffer (
                   NumberHandles,
                   Buffer
                   );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %r\n", __FUNCTION__, Status));
   return Status;
 }
 
@@ -166,6 +175,9 @@ FvbNotificationEvent (
   EFI_FAULT_TOLERANT_WRITE_PROTOCOL       *FtwProtocol;
   EFI_FTW_DEVICE                          *FtwDevice;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Event=%p Context=%p\n", __FUNCTION__,
+    Event, Context));
+
   //
   // Just return to avoid installing FaultTolerantWriteProtocol again
   // if Fault Tolerant Write protocol has been installed.
@@ -176,6 +188,7 @@ FvbNotificationEvent (
                   (VOID **) &FtwProtocol
                   );
   if (!EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return ;
   }
 
@@ -185,6 +198,7 @@ FvbNotificationEvent (
   FtwDevice = (EFI_FTW_DEVICE *)Context;
   Status = InitFtwProtocol (FtwDevice);
   if (EFI_ERROR(Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
     return ;
   }                          
     
@@ -202,6 +216,7 @@ FvbNotificationEvent (
   Status = gBS->CloseEvent (Event);
   ASSERT_EFI_ERROR (Status);
   
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 3: %r\n", __FUNCTION__, Status));
   return;
 }
 
@@ -227,11 +242,14 @@ FaultTolerantWriteInitialize (
   EFI_STATUS                              Status;
   EFI_FTW_DEVICE                          *FtwDevice;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   //
   // Allocate private data structure for FTW protocol and do some initialization
   //
   Status = InitFtwDevice (&FtwDevice);
   if (EFI_ERROR(Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return Status;
   }
 
@@ -246,5 +264,6 @@ FaultTolerantWriteInitialize (
     &mFvbRegistration
     );
   
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c
index b3352bb..436de4c 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/FtwMisc.c
@@ -35,6 +35,9 @@ IsErasedFlashBuffer (
   UINT8   *Ptr;
   UINTN   Index;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Buffer=%p BufferSize=0x%Lx\n",
+    __FUNCTION__, Buffer, (UINT64)BufferSize));
+
   Ptr     = Buffer;
   IsEmpty = TRUE;
   for (Index = 0; Index < BufferSize; Index += 1) {
@@ -44,6 +47,7 @@ IsErasedFlashBuffer (
     }
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit, IsEmpty=%d\n", __FUNCTION__, IsEmpty));
   return IsEmpty;
 }
 
@@ -66,12 +70,17 @@ FtwEraseBlock (
   EFI_LBA                             Lba
   )
 {
-  return FvBlock->EraseBlocks (
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx\n", __FUNCTION__, (UINT64)Lba));
+  Status = FvBlock->EraseBlocks (
                     FvBlock,
                     Lba,
                     FtwDevice->NumberOfSpareBlock,
                     EFI_LBA_LIST_TERMINATOR
                     );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %r\n", __FUNCTION__, Status));
+  return Status;
 }
 
 /**
@@ -96,12 +105,17 @@ FtwEraseSpareBlock (
   IN EFI_FTW_DEVICE   *FtwDevice
   )
 {
-  return FtwDevice->FtwBackupFvb->EraseBlocks (
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+  Status = FtwDevice->FtwBackupFvb->EraseBlocks (
                                     FtwDevice->FtwBackupFvb,
                                     FtwDevice->FtwSpareLba,
                                     FtwDevice->NumberOfSpareBlock,
                                     EFI_LBA_LIST_TERMINATOR
                                     );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %r\n", __FUNCTION__, Status));
+  return Status;
 }
 
 /**
@@ -122,17 +136,22 @@ IsWorkingBlock (
   EFI_LBA                             Lba
   )
 {
+  BOOLEAN Ret;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx\n", __FUNCTION__, (UINT64)Lba));
   //
   // If matching the following condition, the target block is in working block.
   // 1. Target block is on the FV of working block (Using the same FVB protocol instance).
   // 2. Lba falls into the range of working block.
   //
-  return (BOOLEAN)
+  Ret = (BOOLEAN)
     (
       (FvBlock == FtwDevice->FtwFvBlock) &&
       (Lba >= FtwDevice->FtwWorkBlockLba) &&
       (Lba <= FtwDevice->FtwWorkSpaceLba)
     );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %d\n", __FUNCTION__, Ret));
+  return Ret;
 }
 
 /**
@@ -162,6 +181,9 @@ GetFvbByAddress (
   EFI_FIRMWARE_VOLUME_HEADER          *FwVolHeader;
   EFI_HANDLE                          FvbHandle;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Address=0x%Lx\n", __FUNCTION__,
+    (UINT64)Address));
+
   *FvBlock  = NULL;
   FvbHandle = NULL;
   //
@@ -169,6 +191,7 @@ GetFvbByAddress (
   //
   Status = GetFvbCountAndBuffer (&HandleCount, &HandleBuffer);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return NULL;
   }
   //
@@ -196,6 +219,7 @@ GetFvbByAddress (
   }
 
   FreePool (HandleBuffer);
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return FvbHandle;
 }
 
@@ -227,12 +251,16 @@ IsBootBlock (
   BOOLEAN                             IsSwapped;
   EFI_HANDLE                          FvbHandle;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx\n", __FUNCTION__, (UINT64)Lba));
+
   if (!FeaturePcdGet(PcdFullFtwServiceEnable)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return FALSE;
   }
 
   Status = FtwGetSarProtocol ((VOID **) &SarProtocol);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
     return FALSE;
   }
   //
@@ -246,11 +274,13 @@ IsBootBlock (
                           &BackupBlockSize
                           );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3: %r\n", __FUNCTION__, Status));
     return FALSE;
   }
 
   Status = SarProtocol->GetSwapState (SarProtocol, &IsSwapped);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
     return FALSE;
   }
   //
@@ -263,11 +293,14 @@ IsBootBlock (
   }
 
   if (FvbHandle == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 5\n", __FUNCTION__));
     return FALSE;
   }
   //
   // Compare the Fvb
   //
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 6: %d\n", __FUNCTION__,
+    FvBlock == BootFvb));
   return (BOOLEAN) (FvBlock == BootFvb);
 }
 
@@ -313,7 +346,10 @@ FlushSpareBlockToBootBlock (
   EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *BootFvb;
   EFI_LBA                             BootLba;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   if (!FeaturePcdGet(PcdFullFtwServiceEnable)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_UNSUPPORTED;
   }
 
@@ -322,6 +358,7 @@ FlushSpareBlockToBootBlock (
   //
   Status = FtwGetSarProtocol ((VOID **) &SarProtocol);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
     return Status;
   }
   //
@@ -330,6 +367,7 @@ FlushSpareBlockToBootBlock (
   Length = FtwDevice->SpareAreaLength;
   Buffer  = AllocatePool (Length);
   if (Buffer == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
     return EFI_OUT_OF_RESOURCES;
   }
   //
@@ -339,6 +377,7 @@ FlushSpareBlockToBootBlock (
   if (EFI_ERROR (Status)) {
     DEBUG ((EFI_D_ERROR, "Ftw: Get Top Swapped status - %r\n", Status));
     FreePool (Buffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -348,6 +387,7 @@ FlushSpareBlockToBootBlock (
     //
     if (GetFvbByAddress (FtwDevice->SpareAreaAddress + FtwDevice->SpareAreaLength, &BootFvb) == NULL) {
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 5\n", __FUNCTION__));
       return EFI_ABORTED;
     }
     //
@@ -366,6 +406,7 @@ FlushSpareBlockToBootBlock (
                           );
       if (EFI_ERROR (Status)) {
         FreePool (Buffer);
+        DEBUG ((DEBUG_VERBOSE, "%a: exit 6: %r\n", __FUNCTION__, Status));
         return Status;
       }
 
@@ -387,6 +428,7 @@ FlushSpareBlockToBootBlock (
                                           );
       if (EFI_ERROR (Status)) {
         FreePool (Buffer);
+        DEBUG ((DEBUG_VERBOSE, "%a: exit 7: %r\n", __FUNCTION__, Status));
         return Status;
       }
 
@@ -398,6 +440,7 @@ FlushSpareBlockToBootBlock (
     Status = SarProtocol->SetSwapState (SarProtocol, TRUE);
     if (EFI_ERROR (Status)) {
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 8: %r\n", __FUNCTION__, Status));
       return Status;
     }
   }
@@ -408,6 +451,7 @@ FlushSpareBlockToBootBlock (
   Status = FtwEraseSpareBlock (FtwDevice);
   if (EFI_ERROR (Status)) {
     FreePool (Buffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 9: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -426,6 +470,7 @@ FlushSpareBlockToBootBlock (
     if (EFI_ERROR (Status)) {
       DEBUG ((EFI_D_ERROR, "Ftw: FVB Write boot block - %r\n", Status));
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 10: %r\n", __FUNCTION__, Status));
       return Status;
     }
 
@@ -439,6 +484,7 @@ FlushSpareBlockToBootBlock (
   //
   Status = SarProtocol->SetSwapState (SarProtocol, FALSE);
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 11: %r\n", __FUNCTION__, Status));
   return Status;
 }
 
@@ -472,7 +518,10 @@ FlushSpareBlockToTargetBlock (
   UINT8       *Ptr;
   UINTN       Index;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx\n", __FUNCTION__, (UINT64)Lba));
+
   if ((FtwDevice == NULL) || (FvBlock == NULL)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_INVALID_PARAMETER;
   }
   //
@@ -481,6 +530,7 @@ FlushSpareBlockToTargetBlock (
   Length = FtwDevice->SpareAreaLength;
   Buffer  = AllocatePool (Length);
   if (Buffer == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
     return EFI_OUT_OF_RESOURCES;
   }
   //
@@ -498,6 +548,7 @@ FlushSpareBlockToTargetBlock (
                                         );
     if (EFI_ERROR (Status)) {
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 3: %r\n", __FUNCTION__, Status));
       return Status;
     }
 
@@ -509,6 +560,7 @@ FlushSpareBlockToTargetBlock (
   Status = FtwEraseBlock (FtwDevice, FvBlock, Lba);
   if (EFI_ERROR (Status)) {
     FreePool (Buffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -521,6 +573,7 @@ FlushSpareBlockToTargetBlock (
     if (EFI_ERROR (Status)) {
       DEBUG ((EFI_D_ERROR, "Ftw: FVB Write block - %r\n", Status));
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 5: %r\n", __FUNCTION__, Status));
       return Status;
     }
 
@@ -529,6 +582,7 @@ FlushSpareBlockToTargetBlock (
 
   FreePool (Buffer);
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 6: %r\n", __FUNCTION__, Status));
   return Status;
 }
 
@@ -564,12 +618,17 @@ FlushSpareBlockToWorkingBlock (
   UINTN                                   Index;
   EFI_LBA                                 WorkSpaceLbaOffset;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+  Status = EFI_SUCCESS;
+
   //
   // Allocate a memory buffer
   //
   Length = FtwDevice->SpareAreaLength;
   Buffer  = AllocatePool (Length);
   if (Buffer == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -603,6 +662,8 @@ FlushSpareBlockToWorkingBlock (
                                         );
     if (EFI_ERROR (Status)) {
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return Status;
     }
 
@@ -634,6 +695,8 @@ FlushSpareBlockToWorkingBlock (
             );
   if (EFI_ERROR (Status)) {
     FreePool (Buffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ABORTED;
   }
 
@@ -645,6 +708,8 @@ FlushSpareBlockToWorkingBlock (
   Status = FtwEraseBlock (FtwDevice, FtwDevice->FtwFvBlock, FtwDevice->FtwWorkBlockLba);
   if (EFI_ERROR (Status)) {
     FreePool (Buffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ABORTED;
   }
   //
@@ -663,6 +728,8 @@ FlushSpareBlockToWorkingBlock (
     if (EFI_ERROR (Status)) {
       DEBUG ((EFI_D_ERROR, "Ftw: FVB Write block - %r\n", Status));
       FreePool (Buffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return Status;
     }
 
@@ -686,12 +753,16 @@ FlushSpareBlockToWorkingBlock (
             WORKING_BLOCK_VALID
             );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ABORTED;
   }
 
   FtwDevice->FtwWorkSpaceHeader->WorkingBlockInvalid = FTW_INVALID_STATE;
   FtwDevice->FtwWorkSpaceHeader->WorkingBlockValid = FTW_VALID_STATE;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -725,12 +796,17 @@ FtwUpdateFvState (
   UINT8       State;
   UINTN       Length;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx NewBit=%d\n",
+    __FUNCTION__, (UINT64)Lba, (UINT64)Offset, NewBit));
+
   //
   // Read state from device, assume State is only one byte.
   //
   Length  = sizeof (UINT8);
   Status  = FvBlock->Read (FvBlock, Lba, Offset, &Length, &State);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ABORTED;
   }
 
@@ -744,6 +820,8 @@ FtwUpdateFvState (
   Length  = sizeof (UINT8);
   Status  = FvBlock->Write (FvBlock, Lba, Offset, &Length, &State);
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return Status;
 }
 
@@ -770,6 +848,11 @@ FtwGetLastWriteHeader (
 {
   UINTN                           Offset;
   EFI_FAULT_TOLERANT_WRITE_HEADER *FtwHeader;
+  EFI_STATUS                      Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, FtwWorkSpaceSize=0x%Lx\n", __FUNCTION__,
+    (UINT64)FtwWorkSpaceSize));
+  Status = EFI_SUCCESS;
 
   *FtwWriteHeader = NULL;
   FtwHeader       = (EFI_FAULT_TOLERANT_WRITE_HEADER *) (FtwWorkSpaceHeader + 1);
@@ -782,6 +865,8 @@ FtwGetLastWriteHeader (
     //
     if (Offset >= FtwWorkSpaceSize) {
       *FtwWriteHeader = FtwHeader;
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_ABORTED;
     }
 
@@ -792,6 +877,8 @@ FtwGetLastWriteHeader (
   //
   *FtwWriteHeader = FtwHeader;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -816,6 +903,10 @@ FtwGetLastWriteRecord (
 {
   UINTN                           Index;
   EFI_FAULT_TOLERANT_WRITE_RECORD *FtwRecord;
+  EFI_STATUS                      Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+  Status = EFI_SUCCESS;
 
   *FtwWriteRecord = NULL;
   FtwRecord       = (EFI_FAULT_TOLERANT_WRITE_RECORD *) (FtwWriteHeader + 1);
@@ -829,6 +920,8 @@ FtwGetLastWriteRecord (
       // The last write record is found
       //
       *FtwWriteRecord = FtwRecord;
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_SUCCESS;
     }
 
@@ -846,9 +939,13 @@ FtwGetLastWriteRecord (
   //
   if (Index == FtwWriteHeader->NumberOfWrites) {
     *FtwWriteRecord = (EFI_FAULT_TOLERANT_WRITE_RECORD *) ((UINTN) FtwRecord - FTW_RECORD_SIZE (FtwWriteHeader->PrivateDataSize));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_SUCCESS;
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_ABORTED;
 }
 
@@ -899,10 +996,13 @@ IsLastRecordOfWrites (
   UINT8 *Head;
   UINT8 *Ptr;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   Head  = (UINT8 *) FtwHeader;
   Ptr   = (UINT8 *) FtwRecord;
 
   Head += FTW_WRITE_TOTAL_SIZE (FtwHeader->NumberOfWrites - 1, FtwHeader->PrivateDataSize);
+  DEBUG ((DEBUG_VERBOSE, "%a: exit: %d\n", __FUNCTION__, Head == Ptr));
   return (BOOLEAN) (Head == Ptr);
 }
 
@@ -923,15 +1023,22 @@ GetPreviousRecordOfWrites (
   )
 {
   UINT8 *Ptr;
+  EFI_STATUS Status = EFI_SUCCESS;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
 
   if (IsFirstRecordOfWrites (FtwHeader, *FtwRecord)) {
     *FtwRecord = NULL;
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ACCESS_DENIED;
   }
 
   Ptr = (UINT8 *) (*FtwRecord);
   Ptr -= FTW_RECORD_SIZE (FtwHeader->PrivateDataSize);
   *FtwRecord = (EFI_FAULT_TOLERANT_WRITE_RECORD *) Ptr;
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -951,13 +1058,18 @@ InitFtwDevice (
   )
 {
   EFI_FTW_DEVICE                   *FtwDevice;
-  
+  EFI_STATUS Status = EFI_SUCCESS;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+    
   //
   // Allocate private data of this driver,
   // Including the FtwWorkSpace[FTW_WORK_SPACE_SIZE].
   //
   FtwDevice = AllocateZeroPool (sizeof (EFI_FTW_DEVICE) + PcdGet32 (PcdFlashNvStorageFtwWorkingSize));
   if (FtwDevice == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -969,6 +1081,8 @@ InitFtwDevice (
   if ((FtwDevice->WorkSpaceLength == 0) || (FtwDevice->SpareAreaLength == 0)) {
     DEBUG ((EFI_D_ERROR, "Ftw: Workspace or Spare block does not exist!\n"));
     FreePool (FtwDevice);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_INVALID_PARAMETER;
   }
 
@@ -989,6 +1103,8 @@ InitFtwDevice (
   }  
 
   *FtwData = FtwDevice;
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -1019,11 +1135,15 @@ FindFvbForFtw (
   EFI_FV_BLOCK_MAP_ENTRY              *FvbMapEntry;
   UINT32                              LbaIndex;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   //
   // Get all FVB handle.
   //
   Status = GetFvbCountAndBuffer (&HandleCount, &HandleBuffer);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_NOT_FOUND;
   }
 
@@ -1135,9 +1255,13 @@ FindFvbForFtw (
 
   if ((FtwDevice->FtwBackupFvb == NULL) || (FtwDevice->FtwFvBlock == NULL) ||
     (FtwDevice->FtwWorkSpaceLba == (EFI_LBA) (-1)) || (FtwDevice->FtwSpareLba == (EFI_LBA) (-1))) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ABORTED;
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -1164,11 +1288,15 @@ InitFtwProtocol (
   EFI_HANDLE                          FvbHandle;
   EFI_LBA                             WorkSpaceLbaOffset;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   //
   // Find the right SMM Fvb protocol instance for FTW.
   //
   Status = FindFvbForFtw (FtwDevice);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_NOT_FOUND;
   }  
   
@@ -1317,6 +1445,8 @@ InitFtwProtocol (
   FtwDevice->FtwInstance.Abort           = FtwAbort;
   FtwDevice->FtwInstance.GetLastWrite    = FtwGetLastWrite;
     
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
diff --git a/MdeModulePkg/Universal/FaultTolerantWriteDxe/UpdateWorkingBlock.c b/MdeModulePkg/Universal/FaultTolerantWriteDxe/UpdateWorkingBlock.c
index a5fa12b..85a3a2d 100644
--- a/MdeModulePkg/Universal/FaultTolerantWriteDxe/UpdateWorkingBlock.c
+++ b/MdeModulePkg/Universal/FaultTolerantWriteDxe/UpdateWorkingBlock.c
@@ -31,6 +31,7 @@ InitializeLocalWorkSpaceHeader (
 {
   EFI_STATUS                              Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   //
   // Check signature with gEdkiiWorkingBlockSignatureGuid.
   //
@@ -38,6 +39,7 @@ InitializeLocalWorkSpaceHeader (
     //
     // The local work space header has been initialized.
     //
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return;
   }
 
@@ -73,6 +75,8 @@ InitializeLocalWorkSpaceHeader (
 
   mWorkingBlockHeader.WorkingBlockValid    = FTW_VALID_STATE;
   mWorkingBlockHeader.WorkingBlockInvalid  = FTW_INVALID_STATE;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
 }
 
 /**
@@ -90,15 +94,20 @@ IsValidWorkSpace (
   IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingHeader
   )
 {
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   if (WorkingHeader == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return FALSE;
   }
 
   if (CompareMem (WorkingHeader, &mWorkingBlockHeader, sizeof (EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER)) == 0) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
     return TRUE;
   }
 
   DEBUG ((EFI_D_ERROR, "Ftw: Work block header check error\n"));
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
   return FALSE;
 }
 
@@ -116,12 +125,15 @@ InitWorkSpaceHeader (
   IN EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingHeader
   )
 {
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   if (WorkingHeader == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_INVALID_PARAMETER;
   }
 
   CopyMem (WorkingHeader, &mWorkingBlockHeader, sizeof (EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER));
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -143,6 +155,7 @@ WorkSpaceRefresh (
   UINTN                           Length;
   UINTN                           RemainingSpaceSize;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   //
   // Initialize WorkSpace as FTW_ERASED_BYTE
   //
@@ -164,6 +177,7 @@ WorkSpaceRefresh (
                                     FtwDevice->FtwWorkSpace
                                     );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -189,6 +203,7 @@ WorkSpaceRefresh (
     Status = FtwReclaimWorkSpace (FtwDevice, TRUE);
     if (EFI_ERROR (Status)) {
       DEBUG ((EFI_D_ERROR, "Ftw: Reclaim workspace - %r\n", Status));
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
     //
@@ -203,6 +218,7 @@ WorkSpaceRefresh (
                                       FtwDevice->FtwWorkSpace
                                       );
     if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 3: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -212,6 +228,7 @@ WorkSpaceRefresh (
               &FtwDevice->FtwLastWriteHeader
               );
     if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
   }
@@ -223,9 +240,11 @@ WorkSpaceRefresh (
             &FtwDevice->FtwLastWriteRecord
             );
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 5: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 6\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -258,6 +277,8 @@ FtwReclaimWorkSpace (
   UINT8                                   *Ptr;
   EFI_LBA                                 WorkSpaceLbaOffset;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, PreserveRecord=%d\n", __FUNCTION__,
+    PreserveRecord));
   DEBUG ((EFI_D_INFO, "Ftw: start to reclaim work space\n"));
 
   WorkSpaceLbaOffset = FtwDevice->FtwWorkSpaceLba - FtwDevice->FtwWorkBlockLba;
@@ -268,6 +289,7 @@ FtwReclaimWorkSpace (
   TempBufferSize = FtwDevice->SpareAreaLength;
   TempBuffer     = AllocateZeroPool (TempBufferSize);
   if (TempBuffer == NULL) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -283,6 +305,7 @@ FtwReclaimWorkSpace (
                                           );
     if (EFI_ERROR (Status)) {
       FreePool (TempBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 2: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -361,6 +384,7 @@ FtwReclaimWorkSpace (
   SpareBuffer     = AllocatePool (SpareBufferSize);
   if (SpareBuffer == NULL) {
     FreePool (TempBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 3\n", __FUNCTION__));
     return EFI_OUT_OF_RESOURCES;
   }
 
@@ -377,6 +401,7 @@ FtwReclaimWorkSpace (
     if (EFI_ERROR (Status)) {
       FreePool (TempBuffer);
       FreePool (SpareBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 4: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -399,6 +424,7 @@ FtwReclaimWorkSpace (
     if (EFI_ERROR (Status)) {
       FreePool (TempBuffer);
       FreePool (SpareBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 5: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -420,6 +446,7 @@ FtwReclaimWorkSpace (
             );
   if (EFI_ERROR (Status)) {
     FreePool (SpareBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 6: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
   //
@@ -436,6 +463,7 @@ FtwReclaimWorkSpace (
             );
   if (EFI_ERROR (Status)) {
     FreePool (SpareBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 7: %r\n", __FUNCTION__, Status));
     return EFI_ABORTED;
   }
 
@@ -447,6 +475,7 @@ FtwReclaimWorkSpace (
   Status = FlushSpareBlockToWorkingBlock (FtwDevice);
   if (EFI_ERROR (Status)) {
     FreePool (SpareBuffer);
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 8: %r\n", __FUNCTION__, Status));
     return Status;
   }
   //
@@ -465,6 +494,7 @@ FtwReclaimWorkSpace (
                                         );
     if (EFI_ERROR (Status)) {
       FreePool (SpareBuffer);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit 9: %r\n", __FUNCTION__, Status));
       return EFI_ABORTED;
     }
 
@@ -475,5 +505,6 @@ FtwReclaimWorkSpace (
 
   DEBUG ((EFI_D_INFO, "Ftw: reclaim work space successfully\n"));
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 10\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
diff --git a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FvbInfo.c b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FvbInfo.c
index 72845f9..e9f4254 100644
--- a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FvbInfo.c
+++ b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FvbInfo.c
@@ -112,6 +112,10 @@ GetFvbInfo (
 {
   STATIC BOOLEAN Checksummed = FALSE;
   UINTN Index;
+  EFI_STATUS Status = EFI_SUCCESS;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, FvLength=0x%Lx\n", __FUNCTION__,
+    FvLength));
 
   if (!Checksummed) {
     for (Index = 0; Index < sizeof (mPlatformFvbMediaInfo) / sizeof (EFI_FVB_MEDIA_INFO); Index += 1) {
@@ -129,9 +133,13 @@ GetFvbInfo (
   for (Index = 0; Index < sizeof (mPlatformFvbMediaInfo) / sizeof (EFI_FVB_MEDIA_INFO); Index += 1) {
     if (mPlatformFvbMediaInfo[Index].FvLength == FvLength) {
       *FvbInfo = &mPlatformFvbMediaInfo[Index].FvbInfo;
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_SUCCESS;
     }
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_NOT_FOUND;
 }
diff --git a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c
index 7d26c41..56d1b73 100644
--- a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c
+++ b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c
@@ -147,6 +147,8 @@ Returns:
   EFI_FW_VOL_INSTANCE *FwhInstance;
   UINTN               Index;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   EfiConvertPointer (0x0, (VOID **) &mFvbModuleGlobal->FvInstance[FVB_VIRTUAL]);
 
   //
@@ -167,6 +169,8 @@ Returns:
   EfiConvertPointer (0x0, (VOID **) &mFvbModuleGlobal->FvbScratchSpace[FVB_VIRTUAL]);
   EfiConvertPointer (0x0, (VOID **) &mFvbModuleGlobal);
   QemuFlashConvertPointers ();
+
+  DEBUG ((DEBUG_VERBOSE, "%a: exit\n", __FUNCTION__));
 }
 
 EFI_STATUS
@@ -196,8 +200,14 @@ Returns:
 --*/
 {
   EFI_FW_VOL_INSTANCE *FwhRecord;
+  EFI_STATUS Status = EFI_SUCCESS;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Instance=0x%Lx, Global=%p, Virtual=%d\n",
+    __FUNCTION__, (UINT64)Instance, Global, Virtual));
 
   if (Instance >= Global->NumFv) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_INVALID_PARAMETER;
   }
   //
@@ -215,6 +225,8 @@ Returns:
 
   *FwhInstance = FwhRecord;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -249,6 +261,9 @@ Returns:
   EFI_FW_VOL_INSTANCE *FwhInstance;
   EFI_STATUS          Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Instance=0x%Lx, Global=%p, Virtual=%d\n",
+    __FUNCTION__, (UINT64)Instance, Global, Virtual));
+
   //
   // Find the right instance of the FVB private data
   //
@@ -256,6 +271,8 @@ Returns:
   ASSERT_EFI_ERROR (Status);
   *Address = FwhInstance->FvBase[Virtual];
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r, Address=0x%Lx\n",
+    __FUNCTION__, __LINE__, Status, (UINT64)*Address));
   return EFI_SUCCESS;
 }
 
@@ -289,6 +306,9 @@ Returns:
   EFI_FW_VOL_INSTANCE *FwhInstance;
   EFI_STATUS          Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Instance=0x%Lx, Global=%p, Virtual=%d\n",
+    __FUNCTION__, (UINT64)Instance, Global, Virtual));
+
   //
   // Find the right instance of the FVB private data
   //
@@ -296,6 +316,8 @@ Returns:
   ASSERT_EFI_ERROR (Status);
   *Attributes = FwhInstance->VolumeHeader.Attributes;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r, Attributes=0x%Lx\n",
+    __FUNCTION__, __LINE__, Status, (UINT64)*Attributes));
   return EFI_SUCCESS;
 }
 
@@ -343,6 +365,10 @@ Returns:
   EFI_FV_BLOCK_MAP_ENTRY  *BlockMap;
   EFI_STATUS              Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Instance=0x%Lx, Global=%p, Virtual=%d, "
+    "Lba=0x%Lx\n", __FUNCTION__, (UINT64)Instance, Global, Virtual,
+    (UINT64)Lba));
+
   //
   // Find the right instance of the FVB private data
   //
@@ -361,6 +387,8 @@ Returns:
     BlockLength = BlockMap->Length;
 
     if (NumBlocks == 0 || BlockLength == 0) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
 
@@ -373,16 +401,24 @@ Returns:
       Offset = Offset + (UINTN) MultU64x32 ((Lba - StartLba), BlockLength);
       if (LbaAddress != NULL) {
         *LbaAddress = FwhInstance->FvBase[Virtual] + Offset;
+        DEBUG ((DEBUG_VERBOSE, "%a: LbaAddress=0x%Lx\n", __FUNCTION__,
+          (UINT64)*LbaAddress));
       }
 
       if (LbaLength != NULL) {
         *LbaLength = BlockLength;
+        DEBUG ((DEBUG_VERBOSE, "%a: LbaLength=0x%Lx\n", __FUNCTION__,
+          (UINT64)*LbaLength));
       }
 
       if (NumOfBlocks != NULL) {
         *NumOfBlocks = (UINTN) (NextLba - Lba);
+        DEBUG ((DEBUG_VERBOSE, "%a: NumOfBlocks=0x%Lx\n", __FUNCTION__,
+          (UINT64)*NumOfBlocks));
       }
 
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_SUCCESS;
     }
 
@@ -434,6 +470,10 @@ Returns:
   EFI_STATUS            Status;
   EFI_FVB_ATTRIBUTES_2  UnchangedAttributes;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Instance=0x%Lx, Global=%p, Virtual=%d, "
+    "Attributes=0x%Lx\n", __FUNCTION__, (UINT64)Instance, Global, Virtual,
+    (UINTN)*Attributes));
+
   //
   // Find the right instance of the FVB private data
   //
@@ -467,6 +507,8 @@ Returns:
   // Some attributes of FV is read only can *not* be set
   //
   if ((OldAttributes & UnchangedAttributes) ^ (*Attributes & UnchangedAttributes)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_INVALID_PARAMETER;
   }
   //
@@ -474,6 +516,8 @@ Returns:
   //
   if (OldAttributes & EFI_FVB2_LOCK_STATUS) {
     if (OldStatus ^ NewStatus) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_ACCESS_DENIED;
     }
   }
@@ -482,6 +526,8 @@ Returns:
   //
   if ((Capabilities & EFI_FVB2_READ_DISABLED_CAP) == 0) {
     if ((NewStatus & EFI_FVB2_READ_STATUS) == 0) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
   }
@@ -490,6 +536,8 @@ Returns:
   //
   if ((Capabilities & EFI_FVB2_READ_ENABLED_CAP) == 0) {
     if (NewStatus & EFI_FVB2_READ_STATUS) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
   }
@@ -498,6 +546,8 @@ Returns:
   //
   if ((Capabilities & EFI_FVB2_WRITE_DISABLED_CAP) == 0) {
     if ((NewStatus & EFI_FVB2_WRITE_STATUS) == 0) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
   }
@@ -506,6 +556,8 @@ Returns:
   //
   if ((Capabilities & EFI_FVB2_WRITE_ENABLED_CAP) == 0) {
     if (NewStatus & EFI_FVB2_WRITE_STATUS) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
   }
@@ -514,6 +566,8 @@ Returns:
   //
   if ((Capabilities & EFI_FVB2_LOCK_CAP) == 0) {
     if (NewStatus & EFI_FVB2_LOCK_STATUS) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
   }
@@ -522,6 +576,8 @@ Returns:
   *AttribPtr  = (*AttribPtr) | NewStatus;
   *Attributes = *AttribPtr;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r, Attributes=0x%Lx\n",
+    __FUNCTION__, __LINE__, Status, (UINTN)*Attributes));
   return EFI_SUCCESS;
 }
 
@@ -553,10 +609,16 @@ Returns:
 --*/
 {
   EFI_FW_VOL_BLOCK_DEVICE *FvbDevice;
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
 
   FvbDevice = FVB_DEVICE_FROM_THIS (This);
 
-  return FvbGetPhysicalAddress (FvbDevice->Instance, Address, mFvbModuleGlobal, EfiGoneVirtual ());
+  Status = FvbGetPhysicalAddress (FvbDevice->Instance, Address, mFvbModuleGlobal, EfiGoneVirtual ());
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
+  return Status;
 }
 
 EFI_STATUS
@@ -589,10 +651,13 @@ Returns:
 --*/
 {
   EFI_FW_VOL_BLOCK_DEVICE *FvbDevice;
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx\n", __FUNCTION__, (UINT64)Lba));
 
   FvbDevice = FVB_DEVICE_FROM_THIS (This);
 
-  return FvbGetLbaAddress (
+  Status = FvbGetLbaAddress (
           FvbDevice->Instance,
           Lba,
           NULL,
@@ -601,6 +666,10 @@ Returns:
           mFvbModuleGlobal,
           EfiGoneVirtual ()
           );
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r BlockSize=0x%Lx "
+    "NumOfBlocks=0x%Lx\n", __FUNCTION__, __LINE__, Status, (UINT64)*BlockSize,
+    (UINT64)*NumOfBlocks));
+  return Status;
 }
 
 EFI_STATUS
@@ -624,10 +693,16 @@ Returns:
 --*/
 {
   EFI_FW_VOL_BLOCK_DEVICE *FvbDevice;
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
 
   FvbDevice = FVB_DEVICE_FROM_THIS (This);
 
-  return FvbGetVolumeAttributes (FvbDevice->Instance, Attributes, mFvbModuleGlobal, EfiGoneVirtual ());
+  Status = FvbGetVolumeAttributes (FvbDevice->Instance, Attributes, mFvbModuleGlobal, EfiGoneVirtual ());
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
+  return Status;
 }
 
 EFI_STATUS
@@ -651,10 +726,16 @@ Returns:
 --*/
 {
   EFI_FW_VOL_BLOCK_DEVICE *FvbDevice;
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
 
   FvbDevice = FVB_DEVICE_FROM_THIS (This);
 
-  return FvbSetVolumeAttributes (FvbDevice->Instance, Attributes, mFvbModuleGlobal, EfiGoneVirtual ());
+  Status = FvbSetVolumeAttributes (FvbDevice->Instance, Attributes, mFvbModuleGlobal, EfiGoneVirtual ());
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r, Attributes=0x%Lx\n",
+    __FUNCTION__, __LINE__, Status, (UINT64)*Attributes));
+  return Status;
 }
 
 EFI_STATUS
@@ -696,6 +777,8 @@ Returns:
   UINTN                   NumOfLba;
   EFI_STATUS              Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   FvbDevice = FVB_DEVICE_FROM_THIS (This);
 
   Status    = GetFvbInstance (FvbDevice->Instance, mFvbModuleGlobal, &FwhInstance, EfiGoneVirtual ());
@@ -718,6 +801,8 @@ Returns:
     //
     if ((NumOfLba == 0) || ((StartingLba + NumOfLba) > NumOfBlocks)) {
       VA_END (args);
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_INVALID_PARAMETER;
     }
   } while (1);
@@ -737,6 +822,8 @@ Returns:
       Status = QemuFlashEraseBlock (StartingLba);
       if (EFI_ERROR (Status)) {
         VA_END (args);
+        DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+          __FUNCTION__, __LINE__, Status));
         return Status;
       }
 
@@ -748,6 +835,8 @@ Returns:
 
   VA_END (args);
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -791,7 +880,16 @@ Returns:
 
 --*/
 {
-  return QemuFlashWrite ((EFI_LBA)Lba, (UINTN)Offset, NumBytes, (UINT8 *)Buffer);
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx NumBytes=0x%Lx "
+    "Buffer=%p\n", __FUNCTION__, (UINT64)Lba, (UINT64)Offset,
+    (UINT64)*NumBytes, Buffer));
+
+  Status = QemuFlashWrite ((EFI_LBA)Lba, (UINTN)Offset, NumBytes, (UINT8 *)Buffer);
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r, NumBytes=0x%Lx\n",
+    __FUNCTION__, __LINE__, Status, (UINT64)*NumBytes));
+  return Status;
 }
 
 EFI_STATUS
@@ -835,7 +933,16 @@ Returns:
 
 --*/
 {
-  return QemuFlashRead ((EFI_LBA)Lba, (UINTN)Offset, NumBytes, (UINT8 *)Buffer);
+  EFI_STATUS Status;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx NumBytes=0x%Lx "
+    "Buffer=%p\n", __FUNCTION__, (UINT64)Lba, (UINT64)Offset,
+    (UINT64)*NumBytes, Buffer));
+
+  Status = QemuFlashRead ((EFI_LBA)Lba, (UINTN)Offset, NumBytes, (UINT8 *)Buffer);
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r, NumBytes=0x%Lx\n",
+    __FUNCTION__, __LINE__, Status, (UINT64)*NumBytes));
+  return Status;
 }
 
 EFI_STATUS
@@ -857,6 +964,9 @@ Returns:
 --*/
 {
   UINT16 Checksum;
+  EFI_STATUS Status = EFI_SUCCESS;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
 
   //
   // Verify the header revision, header signature, length
@@ -868,6 +978,8 @@ Returns:
       (FwVolHeader->FvLength == ((UINTN) -1)) ||
       ((FwVolHeader->HeaderLength & 0x01) != 0)
       ) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_NOT_FOUND;
   }
   
@@ -883,9 +995,13 @@ Returns:
 
     DEBUG ((EFI_D_INFO, "FV@%p Checksum is 0x%x, expected 0x%x\n",
             FwVolHeader, FwVolHeader->Checksum, Expected));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_NOT_FOUND;
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
 
@@ -898,6 +1014,9 @@ MarkMemoryRangeForRuntimeAccess (
 {
   EFI_STATUS                          Status;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, BaseAddress=0x%Lx Length=0x%Lx\n",
+    __FUNCTION__, (UINT64)BaseAddress, Length));
+
   //
   // Mark flash region as runtime memory
   //
@@ -922,6 +1041,8 @@ MarkMemoryRangeForRuntimeAccess (
                   );
   ASSERT_EFI_ERROR (Status);
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return Status;
 }
 
@@ -938,6 +1059,8 @@ InitializeVariableFvHeader (
   UINTN                               WriteLength;
   UINTN                               BlockSize;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   FwVolHeader =
     (EFI_FIRMWARE_VOLUME_HEADER *) (UINTN)
       PcdGet32 (PcdOvmfFlashNvStorageVariableBase);
@@ -994,6 +1117,8 @@ InitializeVariableFvHeader (
     ASSERT (WriteLength == GoodFwVolHeader->HeaderLength);
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return Status;
 }
 
@@ -1028,11 +1153,15 @@ Returns:
   UINTN                               NumOfBlocks;
   EFI_EVENT                           VirtualAddressChangeEvent;
 
-  if (EFI_ERROR (QemuFlashInitialize ())) {
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
+  if (EFI_ERROR ((Status = QemuFlashInitialize ()))) {
     //
     // Return an error so image will be unloaded
     //
     DEBUG ((EFI_D_INFO, "QEMU flash was not detected. Writable FVB is not being installed.\n"));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_WRITE_PROTECTED;
   }
 
@@ -1049,6 +1178,8 @@ Returns:
   Status = InitializeVariableFvHeader ();
   if (EFI_ERROR (Status)) {
     DEBUG ((EFI_D_INFO, "QEMU Flash: Unable to initialize variable FV header\n"));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_WRITE_PROTECTED;
   }
 
@@ -1061,6 +1192,8 @@ Returns:
     Status = GetFvbInfo (Length, &FwVolHeader);
     if (EFI_ERROR (Status)) {
       DEBUG ((EFI_D_INFO, "EFI_ERROR (GetFvbInfo (Length, &FwVolHeader))\n"));
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_WRITE_PROTECTED;
     }
   }
@@ -1223,5 +1356,7 @@ Returns:
   ASSERT_EFI_ERROR (Status);
 
   PcdSetBool (PcdOvmfFlashVariablesEnable, TRUE);
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return EFI_SUCCESS;
 }
diff --git a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/QemuFlash.c b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/QemuFlash.c
index a3fe7d8..32e07e3 100644
--- a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/QemuFlash.c
+++ b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/QemuFlash.c
@@ -43,7 +43,9 @@ QemuFlashConvertPointers (
   VOID
   )
 {
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
   EfiConvertPointer (0x0, (VOID **) &mFlashBase);
+  DEBUG ((DEBUG_VERBOSE, "%a: exit\n", __FUNCTION__));
 }
 
 
@@ -54,7 +56,13 @@ QemuFlashPtr (
   IN        UINTN                               Offset
   )
 {
-  return mFlashBase + (Lba * mFdBlockSize) + Offset;
+  UINT8 *Ret;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx\n", __FUNCTION__,
+    (UINT64)Lba, (UINT64)Offset));
+  Ret = mFlashBase + (Lba * mFdBlockSize) + Offset;
+  DEBUG ((DEBUG_VERBOSE, "%a: exit, Ret=%p\n", __FUNCTION__, Ret));
+  return Ret;
 }
 
 
@@ -78,6 +86,8 @@ QemuFlashDetected (
   UINT8 OriginalUint8;
   UINT8 ProbeUint8;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   FlashDetected = FALSE;
   Ptr = QemuFlashPtr (0, 0);
 
@@ -93,6 +103,7 @@ QemuFlashDetected (
 
   if (Offset >= mFdBlockSize) {
     DEBUG ((EFI_D_INFO, "QEMU Flash: Failed to find probe location\n"));
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return FALSE;
   }
 
@@ -122,6 +133,7 @@ QemuFlashDetected (
 
   DEBUG ((EFI_D_INFO, "QemuFlashDetected => %a\n",
                       FlashDetected ? "Yes" : "No"));
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return FlashDetected;
 }
 
@@ -146,11 +158,16 @@ QemuFlashRead (
 {
   UINT8  *Ptr;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx NumBytes=0x%Lx "
+    "Buffer=%p\n", __FUNCTION__, (UINT64)Lba, (UINT64)Offset,
+    (UINT64)*NumBytes, Buffer));
+
   //
   // Only write to the first 64k. We don't bother saving the FTW Spare
   // block into the flash memory.
   //
   if (Lba >= mFdBlockCount) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_INVALID_PARAMETER;
   }
 
@@ -161,6 +178,7 @@ QemuFlashRead (
 
   CopyMem (Buffer, Ptr, *NumBytes);
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -186,11 +204,16 @@ QemuFlashWrite (
   volatile UINT8  *Ptr;
   UINTN           Loop;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx Offset=0x%Lx NumBytes=0x%Lx "
+    "Buffer=%p\n", __FUNCTION__, (UINT64)Lba, (UINT64)Offset,
+    (UINT64)*NumBytes, Buffer));
+
   //
   // Only write to the first 64k. We don't bother saving the FTW Spare
   // block into the flash memory.
   //
   if (Lba >= mFdBlockCount) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_INVALID_PARAMETER;
   }
 
@@ -211,6 +234,7 @@ QemuFlashWrite (
     *Ptr = READ_ARRAY_CMD;
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -228,13 +252,17 @@ QemuFlashEraseBlock (
 {
   volatile UINT8  *Ptr;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, Lba=0x%Lx\n", __FUNCTION__, (UINT64)Lba));
+
   if (Lba >= mFdBlockCount) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_INVALID_PARAMETER;
   }
 
   Ptr = QemuFlashPtr (Lba, 0);
   *Ptr = BLOCK_ERASE_CMD;
   *Ptr = BLOCK_ERASE_CONFIRM_CMD;
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
@@ -251,15 +279,19 @@ QemuFlashInitialize (
   VOID
   )
 {
+  DEBUG ((DEBUG_VERBOSE, "%a: enter\n", __FUNCTION__));
+
   mFlashBase = (UINT8*)(UINTN) PcdGet32 (PcdOvmfFdBaseAddress);
   mFdBlockSize = PcdGet32 (PcdOvmfFirmwareBlockSize);
   ASSERT(PcdGet32 (PcdOvmfFirmwareFdSize) % mFdBlockSize == 0);
   mFdBlockCount = PcdGet32 (PcdOvmfFirmwareFdSize) / mFdBlockSize;
 
   if (!QemuFlashDetected ()) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit 1\n", __FUNCTION__));
     return EFI_WRITE_PROTECTED;
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit 2\n", __FUNCTION__));
   return EFI_SUCCESS;
 }
 
diff --git a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Reclaim.c b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Reclaim.c
index b20facd..fc85b18 100644
--- a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Reclaim.c
+++ b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Reclaim.c
@@ -118,11 +118,14 @@ FtwVariableSpace (
   UINTN                              FtwBufferSize;
   EFI_FAULT_TOLERANT_WRITE_PROTOCOL  *FtwProtocol;
 
+  DEBUG ((DEBUG_VERBOSE, "%a:%a: enter\n", __FUNCTION__, __FILE__));
   //
   // Locate fault tolerant write protocol.
   //
   Status = GetFtwProtocol((VOID **) &FtwProtocol);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_NOT_FOUND;
   }
   //
@@ -130,6 +133,8 @@ FtwVariableSpace (
   //
   Status = GetFvbInfoByAddress (VariableBase, &FvbHandle, NULL);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return Status;
   }
   //
@@ -137,6 +142,8 @@ FtwVariableSpace (
   //
   Status = GetLbaAndOffsetByAddress (VariableBase, &VarLba, &VarOffset);
   if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
     return EFI_ABORTED;
   }
 
@@ -156,5 +163,7 @@ FtwVariableSpace (
                           (VOID *) VariableBuffer // write buffer
                           );
 
+    DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+      __FUNCTION__, __LINE__, Status));
   return Status;
 }
diff --git a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c
index 28d026a..369e7bb 100644
--- a/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c
+++ b/SecurityPkg/VariableAuthenticated/RuntimeDxe/Variable.c
@@ -776,6 +776,12 @@ Reclaim (
   VARIABLE_HEADER       *UpdatingVariable;
   VARIABLE_HEADER       *UpdatingInDeletedTransition;
 
+  DEBUG ((DEBUG_VERBOSE, "%a: enter, VariableBase=0x%Lx, IsVolatile=%d, "
+    "NewVariableSize=0x%Lx, ReclaimPubKeyStore=%d\n", __FUNCTION__,
+    (UINT64)VariableBase, IsVolatile, (UINTN)NewVariableSize,
+    ReclaimPubKeyStore));
+  Status = EFI_SUCCESS;
+
   UpdatingVariable = NULL;
   UpdatingInDeletedTransition = NULL;
   if (UpdatingPtrTrack != NULL) {
@@ -826,6 +832,8 @@ Reclaim (
     MaximumBufferSize += 1;
     ValidBuffer = AllocatePool (MaximumBufferSize);
     if (ValidBuffer == NULL) {
+      DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+        __FUNCTION__, __LINE__, Status));
       return EFI_OUT_OF_RESOURCES;
     }
   } else {
@@ -1067,6 +1075,8 @@ Done:
     }
   }
 
+  DEBUG ((DEBUG_VERBOSE, "%a: exit @ %d, Status=%r\n",
+    __FUNCTION__, __LINE__, Status));
   return Status;
 }