diff --git a/MdeModulePkg/Core/Dxe/Hand/DriverSupport.c b/MdeModulePkg/Core/Dxe/Hand/DriverSupport.c
index feabf12faf..12a202417c 100644
--- a/MdeModulePkg/Core/Dxe/Hand/DriverSupport.c
+++ b/MdeModulePkg/Core/Dxe/Hand/DriverSupport.c
@@ -68,7 +68,12 @@ CoreConnectController (
   //
   // Make sure ControllerHandle is valid
   //
+  CoreAcquireProtocolLock ();
+
   Status = CoreValidateHandle (ControllerHandle);
+
+  CoreReleaseProtocolLock ();
+
   if (EFI_ERROR (Status)) {
     return Status;
   }
@@ -268,7 +273,12 @@ AddSortedDriverBindingProtocol (
   //
   // Make sure the DriverBindingHandle is valid
   //
+  CoreAcquireProtocolLock ();
+
   Status = CoreValidateHandle (DriverBindingHandle);
+
+  CoreReleaseProtocolLock ();
+
   if (EFI_ERROR (Status)) {
     return;
   }
@@ -746,8 +756,11 @@ CoreDisconnectController (
   //
   // Make sure ControllerHandle is valid
   //
+  CoreAcquireProtocolLock ();
+
   Status = CoreValidateHandle (ControllerHandle);
   if (EFI_ERROR (Status)) {
+    CoreReleaseProtocolLock ();
     return Status;
   }
 
@@ -757,10 +770,13 @@ CoreDisconnectController (
   if (ChildHandle != NULL) {
     Status = CoreValidateHandle (ChildHandle);
     if (EFI_ERROR (Status)) {
+      CoreReleaseProtocolLock ();
       return Status;
     }
   }
 
+  CoreReleaseProtocolLock ();
+
   Handle = ControllerHandle;
 
   //
diff --git a/MdeModulePkg/Core/Dxe/Hand/Handle.c b/MdeModulePkg/Core/Dxe/Hand/Handle.c
index 6eccb41ecb..92979281b7 100644
--- a/MdeModulePkg/Core/Dxe/Hand/Handle.c
+++ b/MdeModulePkg/Core/Dxe/Hand/Handle.c
@@ -53,6 +53,7 @@ CoreReleaseProtocolLock (
 
 /**
   Check whether a handle is a valid EFI_HANDLE
+  The gProtocolDatabaseLock must be owned
 
   @param  UserHandle             The handle to check
 
@@ -72,6 +73,8 @@ CoreValidateHandle (
     return EFI_INVALID_PARAMETER;
   }
 
+  ASSERT_LOCKED(&gProtocolDatabaseLock);
+
   for (Link = gHandleList.BackLink; Link != &gHandleList; Link = Link->BackLink) {
     Handle = CR (Link, IHANDLE, AllHandles, EFI_HANDLE_SIGNATURE);
     if (Handle == (IHANDLE *) UserHandle) {
@@ -720,19 +723,19 @@ CoreUninstallProtocolInterface (
     return EFI_INVALID_PARAMETER;
   }
 
+  //
+  // Lock the protocol database
+  //
+  CoreAcquireProtocolLock ();
+
   //
   // Check that UserHandle is a valid handle
   //
   Status = CoreValidateHandle (UserHandle);
   if (EFI_ERROR (Status)) {
-    return Status;
+    goto Done;
   }
 
-  //
-  // Lock the protocol database
-  //
-  CoreAcquireProtocolLock ();
-
   //
   // Check that Protocol exists on UserHandle, and Interface matches the interface in the database
   //
@@ -1010,12 +1013,17 @@ CoreOpenProtocol (
     return EFI_INVALID_PARAMETER;
   }
 
+  //
+  // Lock the protocol database
+  //
+  CoreAcquireProtocolLock ();
+
   //
   // Check for invalid UserHandle
   //
   Status = CoreValidateHandle (UserHandle);
   if (EFI_ERROR (Status)) {
-    return Status;
+    goto Done;
   }
 
   //
@@ -1025,31 +1033,32 @@ CoreOpenProtocol (
   case EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER :
     Status = CoreValidateHandle (ImageHandle);
     if (EFI_ERROR (Status)) {
-      return Status;
+      goto Done;
     }
     Status = CoreValidateHandle (ControllerHandle);
     if (EFI_ERROR (Status)) {
-      return Status;
+      goto Done;
     }
     if (UserHandle == ControllerHandle) {
-      return EFI_INVALID_PARAMETER;
+      Status = EFI_INVALID_PARAMETER;
+      goto Done;
     }
     break;
   case EFI_OPEN_PROTOCOL_BY_DRIVER :
   case EFI_OPEN_PROTOCOL_BY_DRIVER | EFI_OPEN_PROTOCOL_EXCLUSIVE :
     Status = CoreValidateHandle (ImageHandle);
     if (EFI_ERROR (Status)) {
-      return Status;
+      goto Done;
     }
     Status = CoreValidateHandle (ControllerHandle);
     if (EFI_ERROR (Status)) {
-      return Status;
+      goto Done;
     }
     break;
   case EFI_OPEN_PROTOCOL_EXCLUSIVE :
     Status = CoreValidateHandle (ImageHandle);
     if (EFI_ERROR (Status)) {
-      return Status;
+      goto Done;
     }
     break;
   case EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL :
@@ -1057,13 +1066,10 @@ CoreOpenProtocol (
   case EFI_OPEN_PROTOCOL_TEST_PROTOCOL :
     break;
   default:
-    return EFI_INVALID_PARAMETER;
+    Status = EFI_INVALID_PARAMETER;
+    goto Done;
   }
 
-  //
-  // Lock the protocol database
-  //
-  CoreAcquireProtocolLock ();
 
   //
   // Look at each protocol interface for a match
@@ -1246,32 +1252,33 @@ CoreCloseProtocol (
   LIST_ENTRY          *Link;
   OPEN_PROTOCOL_DATA  *OpenData;
 
+  //
+  // Lock the protocol database
+  //
+  CoreAcquireProtocolLock ();
+
   //
   // Check for invalid parameters
   //
   Status = CoreValidateHandle (UserHandle);
   if (EFI_ERROR (Status)) {
-    return Status;
+    goto Done;
   }
   Status = CoreValidateHandle (AgentHandle);
   if (EFI_ERROR (Status)) {
-    return Status;
+    goto Done;
   }
   if (ControllerHandle != NULL) {
     Status = CoreValidateHandle (ControllerHandle);
     if (EFI_ERROR (Status)) {
-      return Status;
+      goto Done;
     }
   }
   if (Protocol == NULL) {
-    return EFI_INVALID_PARAMETER;
+    Status = EFI_INVALID_PARAMETER;
+    goto Done;
   }
 
-  //
-  // Lock the protocol database
-  //
-  CoreAcquireProtocolLock ();
-
   //
   // Look at each protocol interface for a match
   //
@@ -1443,13 +1450,6 @@ CoreProtocolsPerHandle (
   UINTN                               ProtocolCount;
   EFI_GUID                            **Buffer;
 
-  Status = CoreValidateHandle (UserHandle);
-  if (EFI_ERROR (Status)) {
-    return Status;
-  }
-
-  Handle = (IHANDLE *)UserHandle;
-
   if (ProtocolBuffer == NULL) {
     return EFI_INVALID_PARAMETER;
   }
@@ -1464,6 +1464,13 @@ CoreProtocolsPerHandle (
 
   CoreAcquireProtocolLock ();
 
+  Status = CoreValidateHandle (UserHandle);
+  if (EFI_ERROR (Status)) {
+    goto Done;
+  }
+
+  Handle = (IHANDLE *)UserHandle;
+
   for (Link = Handle->Protocols.ForwardLink; Link != &Handle->Protocols; Link = Link->ForwardLink) {
     ProtocolCount++;
   }
diff --git a/MdeModulePkg/Core/Dxe/Hand/Handle.h b/MdeModulePkg/Core/Dxe/Hand/Handle.h
index 83eb2b9f3a..3f83e3af15 100644
--- a/MdeModulePkg/Core/Dxe/Hand/Handle.h
+++ b/MdeModulePkg/Core/Dxe/Hand/Handle.h
@@ -242,6 +242,7 @@ CoreReleaseProtocolLock (
 
 /**
   Check whether a handle is a valid EFI_HANDLE
+  The gProtocolDatabaseLock must be owned
 
   @param  UserHandle             The handle to check
 
diff --git a/MdeModulePkg/Core/Dxe/Hand/Notify.c b/MdeModulePkg/Core/Dxe/Hand/Notify.c
index 553413a350..d05f95207f 100644
--- a/MdeModulePkg/Core/Dxe/Hand/Notify.c
+++ b/MdeModulePkg/Core/Dxe/Hand/Notify.c
@@ -188,22 +188,21 @@ CoreReinstallProtocolInterface (
   PROTOCOL_INTERFACE        *Prot;
   PROTOCOL_ENTRY            *ProtEntry;
 
-  Status = CoreValidateHandle (UserHandle);
-  if (EFI_ERROR (Status)) {
-    return Status;
-  }
-
   if (Protocol == NULL) {
     return EFI_INVALID_PARAMETER;
   }
 
-  Handle = (IHANDLE *) UserHandle;
-
   //
   // Lock the protocol database
   //
   CoreAcquireProtocolLock ();
 
+  Status = CoreValidateHandle (UserHandle);
+  if (EFI_ERROR (Status)) {
+    goto Done;
+  }
+
+  Handle = (IHANDLE *) UserHandle;
   //
   // Check that Protocol exists on UserHandle, and Interface matches the interface in the database
   //