diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c
index db3082b..de22a10 100644
--- a/arch/um/drivers/chan_kern.c
+++ b/arch/um/drivers/chan_kern.c
@@ -125,7 +125,7 @@
 	return 0;
 }
 
-int open_chan(struct list_head *chans)
+static int open_chan(struct list_head *chans)
 {
 	struct list_head *ele;
 	struct chan *chan;