diff --git a/sys/geom/geom.h b/sys/geom/geom.h
index ab99c508fef..df85fe315ba 100644
--- a/sys/geom/geom.h
+++ b/sys/geom/geom.h
@@ -45,7 +45,7 @@
 #include <sys/ioccom.h>
 #include <sys/sbuf.h>
 
-#ifndef _KERNEL
+#ifdef KERNELSIM
 /*
  * The GEOM subsystem makes a few concessions in order to be able to run as a
  * user-land simulation as well as a kernel component.