Index: /trunk/src/VBox/VMM/PGMSharedPage.cpp
===================================================================
--- /trunk/src/VBox/VMM/PGMSharedPage.cpp	(revision 30246)
+++ /trunk/src/VBox/VMM/PGMSharedPage.cpp	(revision 30247)
@@ -136,4 +136,10 @@
 static DECLCALLBACK(VBOXSTRICTRC) pgmR3SharedModuleRegRendezvous(PVM pVM, PVMCPU pVCpu, void *pvUser)
 {
+    VMCPUID idCpu = *(VMCPUID *)pvUser;
+
+    /* Execute on the VCPU that issued the original request to make sure we're in the right cr3 context. */
+    if (pVCpu->idCpu != idCpu)
+        return VINF_SUCCESS;
+
     /* Flush all pending handy page operations before changing any shared page assignments. */
     int rc = PGMR3PhysAllocateHandyPages(pVM);
@@ -155,6 +161,8 @@
 static DECLCALLBACK(void) pgmR3CheckSharedModulesHelper(PVM pVM)
 {
+    VMCPUID idCpu = VMMGetCpuId(pVM);
+
     /* We must stall other VCPUs as we'd otherwise have to send IPI flush commands for every single change we make. */
-    int rc = VMMR3EmtRendezvous(pVM, VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE, pgmR3SharedModuleRegRendezvous, NULL);
+    int rc = VMMR3EmtRendezvous(pVM, VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE, pgmR3SharedModuleRegRendezvous, &idCpu);
     AssertRC(rc);
 }