diff --git a/arch/um/drivers/mcast_kern.c b/arch/um/drivers/mcast_kern.c
index 822092f149bedb666740b1958b0778cd9ca01b3d..8c4378a76d6333d88d14537ae1c9a3b42b099537 100644
--- a/arch/um/drivers/mcast_kern.c
+++ b/arch/um/drivers/mcast_kern.c
@@ -58,7 +58,7 @@ static const struct net_kern_info mcast_kern_info = {
 	.write			= mcast_write,
 };
 
-int mcast_setup(char *str, char **mac_out, void *data)
+static int mcast_setup(char *str, char **mac_out, void *data)
 {
 	struct mcast_init *init = data;
 	char *port_str = NULL, *ttl_str = NULL, *remain;
diff --git a/arch/um/drivers/mconsole_user.c b/arch/um/drivers/mconsole_user.c
index 13af2f03ed8479ac8f7f17ce4d7389120cdac297..f8cf4c8bedef3eb91f161a6da67e474ae508464d 100644
--- a/arch/um/drivers/mconsole_user.c
+++ b/arch/um/drivers/mconsole_user.c
@@ -39,7 +39,7 @@ static struct mconsole_command commands[] = {
 /* Initialized in mconsole_init, which is an initcall */
 char mconsole_socket_name[256];
 
-int mconsole_reply_v0(struct mc_request *req, char *reply)
+static int mconsole_reply_v0(struct mc_request *req, char *reply)
 {
 	struct iovec iov;
 	struct msghdr msg;
diff --git a/arch/um/drivers/port_user.c b/arch/um/drivers/port_user.c
index addd759026560bb75eb1129e3b1e2818e77cf345..d269ca387f108de63595a5bf46085864668537e6 100644
--- a/arch/um/drivers/port_user.c
+++ b/arch/um/drivers/port_user.c
@@ -153,7 +153,7 @@ struct port_pre_exec_data {
 	int pipe_fd;
 };
 
-void port_pre_exec(void *arg)
+static void port_pre_exec(void *arg)
 {
 	struct port_pre_exec_data *data = arg;