diff --git a/include/linux/pid.h b/include/linux/pid.h
index 8d19903..c21c7e8 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -60,7 +60,7 @@ struct pid
 	/* lists of tasks that use this pid */
 	struct hlist_head tasks[PIDTYPE_MAX];
 	struct rcu_head rcu;
-	int level;
+	unsigned int level;
 	struct upid numbers[1];
 };
 
diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
index fcd61fa..caff528 100644
--- a/include/linux/pid_namespace.h
+++ b/include/linux/pid_namespace.h
@@ -20,7 +20,7 @@ struct pid_namespace {
 	int last_pid;
 	struct task_struct *child_reaper;
 	struct kmem_cache *pid_cachep;
-	int level;
+	unsigned int level;
 	struct pid_namespace *parent;
 #ifdef CONFIG_PROC_FS
 	struct vfsmount *proc_mnt;
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 5ca37fa..98702b4 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -66,7 +66,7 @@ err_alloc:
 	return NULL;
 }
 
-static struct pid_namespace *create_pid_namespace(int level)
+static struct pid_namespace *create_pid_namespace(unsigned int level)
 {
 	struct pid_namespace *ns;
 	int i;