Index: /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideo.cpp
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideo.cpp	(revision 32914)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideo.cpp	(revision 32915)
@@ -2082,5 +2082,5 @@
                 }
                 /* clear the IRQ */
-                HGSMIClearIrq (PrimaryExtension);
+                HGSMIClearIrq (hgsmiFromDeviceExt(PrimaryExtension));
                 return TRUE;
             }
Index: /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideo.h
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideo.h	(revision 32914)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideo.h	(revision 32915)
@@ -916,5 +916,5 @@
     );
 
-void HGSMIClearIrq (PDEVICE_EXTENSION PrimaryExtension);
+void HGSMIClearIrq (PHGSMI_GUEST_INFO pInfo);
 
 #endif /* VBOX_WITH_HGSMI */
Index: /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideoHGSMI.cpp
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideoHGSMI.cpp	(revision 32914)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/VBoxVideoHGSMI.cpp	(revision 32915)
@@ -33,21 +33,21 @@
 #define MEM_TAG 'HVBV'
 
-void HGSMINotifyHostCmdComplete (PDEVICE_EXTENSION PrimaryExtension, HGSMIOFFSET offt)
-{
-    VBoxHGSMIHostWrite(hgsmiFromDeviceExt(PrimaryExtension), offt);
-}
-
-void HGSMIClearIrq (PDEVICE_EXTENSION PrimaryExtension)
-{
-    VBoxHGSMIHostWrite(hgsmiFromDeviceExt(PrimaryExtension), HGSMIOFFSET_VOID);
-}
-
-static void HGSMIHostCmdComplete (PDEVICE_EXTENSION PrimaryExtension, void * pvMem)
-{
-    HGSMIOFFSET offMem = HGSMIPointerToOffset (&hgsmiFromDeviceExt(PrimaryExtension)->areaHostHeap, HGSMIBufferHeaderFromData (pvMem));
+void HGSMINotifyHostCmdComplete (PHGSMI_GUEST_INFO pInfo, HGSMIOFFSET offt)
+{
+    VBoxHGSMIHostWrite(pInfo, offt);
+}
+
+void HGSMIClearIrq (PHGSMI_GUEST_INFO pInfo)
+{
+    VBoxHGSMIHostWrite(pInfo, HGSMIOFFSET_VOID);
+}
+
+static void HGSMIHostCmdComplete (PHGSMI_GUEST_INFO pInfo, void * pvMem)
+{
+    HGSMIOFFSET offMem = HGSMIPointerToOffset (&pInfo->areaHostHeap, HGSMIBufferHeaderFromData (pvMem));
     Assert(offMem != HGSMIOFFSET_VOID);
     if(offMem != HGSMIOFFSET_VOID)
     {
-        HGSMINotifyHostCmdComplete (PrimaryExtension, offMem);
+        HGSMINotifyHostCmdComplete (pInfo, offMem);
     }
 }
@@ -63,5 +63,5 @@
         /* failure means the command was not submitted to the handler for some reason
          * it's our responsibility to notify its completion in this case */
-        HGSMINotifyHostCmdComplete(PrimaryExtension, offBuffer);
+        HGSMINotifyHostCmdComplete(hgsmiFromDeviceExt(PrimaryExtension), offBuffer);
     }
     /* if the cmd succeeded it's responsibility of the callback to complete it */
@@ -1353,5 +1353,5 @@
 {
     PDEVICE_EXTENSION PrimaryExtension = ((PDEVICE_EXTENSION)hHGSMI)->pPrimary;
-    HGSMIHostCmdComplete (PrimaryExtension, pCmd);
+    HGSMIHostCmdComplete (hgsmiFromDeviceExt(PrimaryExtension), pCmd);
 }
 
@@ -1467,5 +1467,5 @@
                             VBVAHOSTCMD * pNext = pCur->u.pNext;
                             pCur->u.pNext = NULL;
-                            HGSMIHostCmdComplete(pCallbacks->PrimaryExtension, pCur);
+                            HGSMIHostCmdComplete(hgsmiFromDeviceExt(pCallbacks->PrimaryExtension), pCur);
                             pCur = pNext;
                             Assert(!pCur);
@@ -1536,5 +1536,5 @@
     }
     /* no handlers were found, need to complete the command here */
-    HGSMIHostCmdComplete(pCallbacks->PrimaryExtension, pvBuffer);
+    HGSMIHostCmdComplete(hgsmiFromDeviceExt(pCallbacks->PrimaryExtension), pvBuffer);
     return VINF_SUCCESS;
 }
Index: /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/wddm/VBoxVideoWddm.cpp
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/wddm/VBoxVideoWddm.cpp	(revision 32914)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Miniport/wddm/VBoxVideoWddm.cpp	(revision 32915)
@@ -896,5 +896,5 @@
         if (bOur)
         {
-            HGSMIClearIrq (pDevExt);
+            HGSMIClearIrq (hgsmiFromDeviceExt(pDevExt));
 #ifdef DEBUG_misha
             /* this is not entirely correct since host may concurrently complete some commands and raise a new IRQ while we are here,