diff --git a/sys/kern/kern_conf.c b/sys/kern/kern_conf.c
index 325c7ef51def..43c026ce0b07 100644
--- a/sys/kern/kern_conf.c
+++ b/sys/kern/kern_conf.c
@@ -357,10 +357,11 @@ remove_dev(dev_t dev)
 	freedev(dev);
 }
 
-char *
+const char *
 devtoname(dev_t dev)
 {
 	char *p;
+	int mynor;
 
 	if (dev->si_name[0] == '#' || dev->si_name[0] == '\0') {
 		p = dev->si_name;
@@ -369,8 +370,11 @@ devtoname(dev_t dev)
 		else
 			sprintf(p, "#%d/", major(dev));
 		p += strlen(p);
-		sprintf(p, minor(dev) > 255 ? "0x%x" : "%d", minor(dev));
+		mynor = minor(dev);
+		if (mynor < 0 || mynor > 255)
+			sprintf(p, "%#x", (u_int)mynor);
+		else
+			sprintf(p, "%d", mynor);
 	}
 	return (dev->si_name);
 }
-
diff --git a/sys/sys/conf.h b/sys/sys/conf.h
index 377d90a17c25..156a192d0d17 100644
--- a/sys/sys/conf.h
+++ b/sys/sys/conf.h
@@ -176,7 +176,7 @@ struct cdevsw {
 	d_poll_t	*d_poll;
 	d_mmap_t	*d_mmap;
 	d_strategy_t	*d_strategy;
-	char		*d_name;	/* base device name, e.g. 'vn' */
+	const char	*d_name;	/* base device name, e.g. 'vn' */
 	d_parms_t	*d_bogoparms;	/* XXX not used */
 	int		d_maj;
 	d_dump_t	*d_dump;
@@ -280,7 +280,7 @@ int	cdevsw_remove __P((struct cdevsw *old));
 dev_t	chrtoblk __P((dev_t dev));
 struct cdevsw *devsw __P((dev_t dev));
 int	devsw_module_handler __P((struct module *mod, int what, void *arg));
-char   *devtoname __P((dev_t dev));
+const char *devtoname __P((dev_t dev));
 void	freedev __P((dev_t dev));
 int	iskmemdev __P((dev_t dev));
 int	iszerodev __P((dev_t dev));
diff --git a/sys/sys/linedisc.h b/sys/sys/linedisc.h
index 377d90a17c25..156a192d0d17 100644
--- a/sys/sys/linedisc.h
+++ b/sys/sys/linedisc.h
@@ -176,7 +176,7 @@ struct cdevsw {
 	d_poll_t	*d_poll;
 	d_mmap_t	*d_mmap;
 	d_strategy_t	*d_strategy;
-	char		*d_name;	/* base device name, e.g. 'vn' */
+	const char	*d_name;	/* base device name, e.g. 'vn' */
 	d_parms_t	*d_bogoparms;	/* XXX not used */
 	int		d_maj;
 	d_dump_t	*d_dump;
@@ -280,7 +280,7 @@ int	cdevsw_remove __P((struct cdevsw *old));
 dev_t	chrtoblk __P((dev_t dev));
 struct cdevsw *devsw __P((dev_t dev));
 int	devsw_module_handler __P((struct module *mod, int what, void *arg));
-char   *devtoname __P((dev_t dev));
+const char *devtoname __P((dev_t dev));
 void	freedev __P((dev_t dev));
 int	iskmemdev __P((dev_t dev));
 int	iszerodev __P((dev_t dev));