Index: /trunk/src/VBox/Devices/PC/DevIoApic.cpp
===================================================================
--- /trunk/src/VBox/Devices/PC/DevIoApic.cpp	(revision 71852)
+++ /trunk/src/VBox/Devices/PC/DevIoApic.cpp	(revision 71853)
@@ -527,4 +527,5 @@
 {
     uint8_t const uIndex = pThis->u8Index;
+    RT_UNTRUSTED_NONVOLATILE_COPY_FENCE();
     if (   uIndex >= IOAPIC_INDIRECT_INDEX_REDIR_TBL_START
         && uIndex <= pThis->u8LastRteRegIdx)
@@ -568,4 +569,5 @@
 {
     uint8_t const uIndex = pThis->u8Index;
+    RT_UNTRUSTED_NONVOLATILE_COPY_FENCE();
     LogFlow(("IOAPIC: ioapicSetData: uIndex=%#x uValue=%#RX32\n", uIndex, uValue));