diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
index cd3f8ac75915..e76b3484fce9 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
@@ -5387,6 +5387,8 @@ l2arc_add_vdev(spa_t *spa, vdev_t *vd)
 
 	ASSERT(!l2arc_vdev_present(vd));
 
+	vdev_ashift_optimize(vd);
+
 	/*
 	 * Create a new l2arc device entry.
 	 */