Index: /trunk/src/VBox/VMM/VMMAll/APICAll.cpp
===================================================================
--- /trunk/src/VBox/VMM/VMMAll/APICAll.cpp	(revision 61556)
+++ /trunk/src/VBox/VMM/VMMAll/APICAll.cpp	(revision 61557)
@@ -1142,4 +1142,7 @@
      * update ISR/TPR transparently. We thus re-calculate the PPR which may be out of sync.
      * See Intel spec. 29.2.2 "Virtual-Interrupt Delivery".
+     *
+     * In all other instances, whenever the TPR or ISR changes, we need to update the PPR
+     * as well (e.g. like we do manually in apicR3InitIpi and by calling apicUpdatePpr).
      */
     PCAPIC pApic = VM_TO_APIC(pVCpu->CTX_SUFF(pVM));