--- a/drivers/gpu/drm/drm_vm.c
+++ b/drivers/gpu/drm/drm_vm.c
@@ -422,6 +422,7 @@ void drm_vm_open_locked(struct drm_device *dev,
 list_add(&vma_entry->head, &dev->vmalist);
 }
 }
+EXPORT_SYMBOL_GPL(drm_vm_open_locked);
 
 static void drm_vm_open(struct vm_area_struct *vma)
 {