diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index c9bbcb2..d08cfe7 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -428,6 +428,8 @@
 	void (*destroy)(struct cgroup_subsys *ss, struct cgroup *cgrp);
 	int (*can_attach)(struct cgroup_subsys *ss, struct cgroup *cgrp,
 			  struct task_struct *tsk, bool threadgroup);
+	void (*cancel_attach)(struct cgroup_subsys *ss, struct cgroup *cgrp,
+			  struct task_struct *tsk, bool threadgroup);
 	void (*attach)(struct cgroup_subsys *ss, struct cgroup *cgrp,
 			struct cgroup *old_cgrp, struct task_struct *tsk,
 			bool threadgroup);