Index: sys/vm/vm_map.c
===================================================================
--- sys/vm/vm_map.c
+++ sys/vm/vm_map.c
@@ -2461,6 +2461,11 @@
 static inline void
 vm_map_clip_end(vm_map_t map, vm_map_entry_t entry, vm_offset_t endaddr)
 {
+	if (!map->system_map)
+		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
+		    "vm_map_clip_end: map %p entry %p end 0x%jx", map, entry,
+		    (uintmax_t)endaddr);
+
 	if (endaddr < entry->end)
 		_vm_map_clip_end(map, entry, endaddr);
 }
@@ -3747,6 +3752,12 @@
 	vm_map_entry_t entry, next_entry;
 
 	VM_MAP_ASSERT_LOCKED(map);
+
+	if (!map->system_map)
+		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
+		    "vm_map_delete: map %p 0x%jx-0x%jx", map, (uintmax_t)start,
+		    (uintmax_t)end);
+
 	if (start == end)
 		return (KERN_SUCCESS);