diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0f4196a..28df707 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1247,8 +1247,8 @@
 		!vma_growsup(vma->vm_next, addr);
 }
 
-extern pid_t
-vm_is_stack(struct task_struct *task, struct vm_area_struct *vma, int in_group);
+extern struct task_struct *task_of_stack(struct task_struct *task,
+				struct vm_area_struct *vma, bool in_group);
 
 extern unsigned long move_page_tables(struct vm_area_struct *vma,
 		unsigned long old_addr, struct vm_area_struct *new_vma,