diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index 9d5cd10..0d36750 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -84,6 +84,7 @@
 extern int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len);
 extern int ptrace_attach(struct task_struct *tsk);
 extern int ptrace_detach(struct task_struct *, unsigned int);
+extern void __ptrace_detach(struct task_struct *, unsigned int);
 extern void ptrace_disable(struct task_struct *);
 extern int ptrace_check_attach(struct task_struct *task, int kill);
 extern int ptrace_request(struct task_struct *child, long request, long addr, long data);