diff --git a/include/mount.h b/include/mount.h
index a13483be6..a6ff4c452 100644
--- a/include/mount.h
+++ b/include/mount.h
@@ -14,7 +14,6 @@ extern struct fstype *find_fstype_by_name(char *fst);
 struct cr_fdset;
 struct ns_id;
 extern struct mount_info * collect_mntinfo(struct ns_id *ns);
-extern int dump_mnt_ns(struct ns_id *ns);
 extern int prepare_mnt_ns(void);
 
 extern int pivot_root(const char *new_root, const char *put_old);
diff --git a/mount.c b/mount.c
index 7d7e8edd4..92f2cefc7 100644
--- a/mount.c
+++ b/mount.c
@@ -843,7 +843,7 @@ err:
 	return NULL;
 }
 
-int dump_mnt_ns(struct ns_id *ns)
+static int dump_mnt_ns(struct ns_id *ns)
 {
 	struct mount_info *pm, *pms;
 	int img_fd = -1, ret = -1;