Index: head/sys/vm/vm_map.c
===================================================================
--- head/sys/vm/vm_map.c
+++ head/sys/vm/vm_map.c
@@ -2109,6 +2109,60 @@
 }
 
 /*
+ *	vm_map_entry_back:
+ *
+ *	Allocate an object to back a map entry.
+ */
+static inline void
+vm_map_entry_back(vm_map_entry_t entry)
+{
+	vm_object_t object;
+
+	KASSERT(entry->object.vm_object == NULL,
+	    ("map entry %p has backing object", entry));
+	KASSERT((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0,
+	    ("map entry %p is a submap", entry));
+	object = vm_object_allocate(OBJT_DEFAULT,
+	    atop(entry->end - entry->start));
+	entry->object.vm_object = object;
+	entry->offset = 0;
+	if (entry->cred != NULL) {
+		object->cred = entry->cred;
+		object->charge = entry->end - entry->start;
+		entry->cred = NULL;
+	}
+}
+
+/*
+ *	vm_map_entry_charge_object
+ *
+ *	If there is no object backing this entry, create one.  Otherwise, if
+ *	the entry has cred, give it to the backing object.
+ */
+static inline void
+vm_map_entry_charge_object(vm_map_t map, vm_map_entry_t entry)
+{
+
+	VM_MAP_ASSERT_LOCKED(map);
+	KASSERT((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0,
+	    ("map entry %p is a submap", entry));
+	if (entry->object.vm_object == NULL && !map->system_map &&
+	    (entry->eflags & MAP_ENTRY_GUARD) == 0)
+		vm_map_entry_back(entry);
+	else if (entry->object.vm_object != NULL &&
+	    ((entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) &&
+	    entry->cred != NULL) {
+		VM_OBJECT_WLOCK(entry->object.vm_object);
+		KASSERT(entry->object.vm_object->cred == NULL,
+		    ("OVERCOMMIT: %s: both cred e %p", __func__, entry));
+		entry->object.vm_object->cred = entry->cred;
+		entry->object.vm_object->charge = entry->end - entry->start;
+		VM_OBJECT_WUNLOCK(entry->object.vm_object);
+		entry->cred = NULL;
+	}
+}
+
+/*
  *	vm_map_clip_start:	[ internal use only ]
  *
  *	Asserts that the given entry begins at or after
@@ -2140,38 +2194,7 @@
 	 * starting address.
 	 */
 	vm_map_simplify_entry(map, entry);
-
-	/*
-	 * If there is no object backing this entry, we might as well create
-	 * one now.  If we defer it, an object can get created after the map
-	 * is clipped, and individual objects will be created for the split-up
-	 * map.  This is a bit of a hack, but is also about the best place to
-	 * put this improvement.
-	 */
-	if (entry->object.vm_object == NULL && !map->system_map &&
-	    (entry->eflags & MAP_ENTRY_GUARD) == 0) {
-		vm_object_t object;
-		object = vm_object_allocate(OBJT_DEFAULT,
-				atop(entry->end - entry->start));
-		entry->object.vm_object = object;
-		entry->offset = 0;
-		if (entry->cred != NULL) {
-			object->cred = entry->cred;
-			object->charge = entry->end - entry->start;
-			entry->cred = NULL;
-		}
-	} else if (entry->object.vm_object != NULL &&
-		   ((entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) &&
-		   entry->cred != NULL) {
-		VM_OBJECT_WLOCK(entry->object.vm_object);
-		KASSERT(entry->object.vm_object->cred == NULL,
-		    ("OVERCOMMIT: vm_entry_clip_start: both cred e %p", entry));
-		entry->object.vm_object->cred = entry->cred;
-		entry->object.vm_object->charge = entry->end - entry->start;
-		VM_OBJECT_WUNLOCK(entry->object.vm_object);
-		entry->cred = NULL;
-	}
-
+	vm_map_entry_charge_object(map, entry);
 	new_entry = vm_map_entry_create(map);
 	*new_entry = *entry;
 
@@ -2222,40 +2245,11 @@
 	KASSERT(entry->start < end && entry->end > end,
 	    ("_vm_map_clip_end: invalid clip of entry %p", entry));
 
-	/*
-	 * If there is no object backing this entry, we might as well create
-	 * one now.  If we defer it, an object can get created after the map
-	 * is clipped, and individual objects will be created for the split-up
-	 * map.  This is a bit of a hack, but is also about the best place to
-	 * put this improvement.
-	 */
-	if (entry->object.vm_object == NULL && !map->system_map &&
-	    (entry->eflags & MAP_ENTRY_GUARD) == 0) {
-		vm_object_t object;
-		object = vm_object_allocate(OBJT_DEFAULT,
-				atop(entry->end - entry->start));
-		entry->object.vm_object = object;
-		entry->offset = 0;
-		if (entry->cred != NULL) {
-			object->cred = entry->cred;
-			object->charge = entry->end - entry->start;
-			entry->cred = NULL;
-		}
-	} else if (entry->object.vm_object != NULL &&
-		   ((entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) &&
-		   entry->cred != NULL) {
-		VM_OBJECT_WLOCK(entry->object.vm_object);
-		KASSERT(entry->object.vm_object->cred == NULL,
-		    ("OVERCOMMIT: vm_entry_clip_end: both cred e %p", entry));
-		entry->object.vm_object->cred = entry->cred;
-		entry->object.vm_object->charge = entry->end - entry->start;
-		VM_OBJECT_WUNLOCK(entry->object.vm_object);
-		entry->cred = NULL;
-	}
 
 	/*
 	 * Create a new entry and insert it AFTER the specified entry
 	 */
+	vm_map_entry_charge_object(map, entry);
 	new_entry = vm_map_entry_create(map);
 	*new_entry = *entry;
 
@@ -3935,16 +3929,8 @@
 			 */
 			object = old_entry->object.vm_object;
 			if (object == NULL) {
-				object = vm_object_allocate(OBJT_DEFAULT,
-					atop(old_entry->end - old_entry->start));
-				old_entry->object.vm_object = object;
-				old_entry->offset = 0;
-				if (old_entry->cred != NULL) {
-					object->cred = old_entry->cred;
-					object->charge = old_entry->end -
-					    old_entry->start;
-					old_entry->cred = NULL;
-				}
+				vm_map_entry_back(old_entry);
+				object = old_entry->object.vm_object;
 			}
 
 			/*