Index: /trunk/src/VBox/Devices/Storage/DevAHCI.cpp
===================================================================
--- /trunk/src/VBox/Devices/Storage/DevAHCI.cpp	(revision 64841)
+++ /trunk/src/VBox/Devices/Storage/DevAHCI.cpp	(revision 64842)
@@ -4651,7 +4651,10 @@
             {
                 AHCIREQ Req;
-                Req.uTag    = idx;
-                Req.fFlags  = AHCI_REQ_IS_ON_STACK;
-                Req.fMapped = false;
+                Req.uTag       = idx;
+                Req.fFlags     = AHCI_REQ_IS_ON_STACK;
+                Req.fMapped    = false;
+                Req.cbTransfer = 0;
+                Req.uOffset    = 0;
+                Req.enmType    = PDMMEDIAEXIOREQTYPE_INVALID;
 
                 bool fContinue = ahciR3CmdPrepare(pAhciPort, &Req);