diff --git a/[refs] b/[refs]
index 1255c53a8b10..40778925a934 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7c8a83b75a38a807d37f5a4398eca2a42c8cf513
+refs/heads/master: b43b1901ad282aeb74161837fb403927102687a1
diff --git a/trunk/virt/kvm/kvm_main.c b/trunk/virt/kvm/kvm_main.c
index 687d113a3e5e..5fed9bfc3cf5 100644
--- a/trunk/virt/kvm/kvm_main.c
+++ b/trunk/virt/kvm/kvm_main.c
@@ -1210,8 +1210,10 @@ int __kvm_set_memory_region(struct kvm *kvm,
 
 	kvm_free_physmem_slot(&old, npages ? &new : NULL);
 	/* Slot deletion case: we have to update the current slot */
+	spin_lock(&kvm->mmu_lock);
 	if (!npages)
 		*memslot = old;
+	spin_unlock(&kvm->mmu_lock);
 #ifdef CONFIG_DMAR
 	/* map the pages in iommu page table */
 	r = kvm_iommu_map_pages(kvm, base_gfn, npages);