diff --git a/[refs] b/[refs]
index 16f59c09a0f2..2640be28cd50 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f0a70c882ea546bbd802643990ceded32c39facc
+refs/heads/master: 9b705f0e98c489b18ba22a6eab9d694b546c8552
diff --git a/trunk/arch/x86/xen/p2m.c b/trunk/arch/x86/xen/p2m.c
index 8db19d50c467..b3b19d43b951 100644
--- a/trunk/arch/x86/xen/p2m.c
+++ b/trunk/arch/x86/xen/p2m.c
@@ -407,8 +407,11 @@ static unsigned long mfn_hash(unsigned long mfn)
 void m2p_add_override(unsigned long mfn, struct page *page)
 {
 	unsigned long flags;
+	unsigned long pfn = page_to_pfn(page);
 	page->private = mfn;
+	page->index = pfn_to_mfn(pfn);
 
+	__set_phys_to_machine(pfn, FOREIGN_FRAME(mfn));
 	spin_lock_irqsave(&m2p_override_lock, flags);
 	list_add(&page->lru,  &m2p_overrides[mfn_hash(mfn)]);
 	spin_unlock_irqrestore(&m2p_override_lock, flags);
@@ -417,9 +420,18 @@ void m2p_add_override(unsigned long mfn, struct page *page)
 void m2p_remove_override(struct page *page)
 {
 	unsigned long flags;
+	unsigned long mfn;
+	unsigned long pfn;
+
+	pfn = page_to_pfn(page);
+	mfn = get_phys_to_machine(pfn);
+	if (mfn == INVALID_P2M_ENTRY || !(mfn & FOREIGN_FRAME_BIT))
+		return;
+
 	spin_lock_irqsave(&m2p_override_lock, flags);
 	list_del(&page->lru);
 	spin_unlock_irqrestore(&m2p_override_lock, flags);
+	__set_phys_to_machine(pfn, page->index);
 }
 
 struct page *m2p_find_override(unsigned long mfn)