diff --git a/tools/mkconfig.c b/tools/mkconfig.c
index d8d09df348..a622743a0a 100644
--- a/tools/mkconfig.c
+++ b/tools/mkconfig.c
@@ -126,17 +126,23 @@ int main(int argc, char **argv, char **envp)
   printf("#ifndef CONFIG_RR_INTERVAL\n");
   printf("# define CONFIG_RR_INTERVAL 0\n");
   printf("#endif\n\n");
-  printf("/* The correct way to disable filesystem supuport is to set the\n");
-  printf(" * number of file descriptors to zero.\n");
+  printf("/* The correct way to disable filesystem supuport is to set the number of\n");
+  printf(" * file descriptors to zero.\n");
   printf(" */\n\n");
   printf("#ifndef CONFIG_NFILE_DESCRIPTORS\n");
   printf("# define CONFIG_NFILE_DESCRIPTORS 0\n");
   printf("#endif\n\n");
-  printf("/* If a console is selected, then make sure that there are\n");
-  printf(" * resources for 3 file descriptors and, if any streams are\n");
-  printf(" * selected, also for 3 file streams.\n");
+  printf("/* If a console is selected, then make sure that there are resources for\n");
+  printf(" * three file descriptors and, if any streams are selected, also for three\n");
+  printf(" * file streams.\n");
+  printf(" *\n");
+  printf(" * CONFIG_DEV_CONSOLE means that a builtin console device exists at /dev/console\n");
+  printf(" * and can be opened during boot-up.  Other consoles, such as USB consoles, may\n");
+  printf(" * not exist at boot-upand have to be handled in a different way.  Three file\n");
+  printf(" * descriptors and three file streams are still needed.\n");
   printf(" */\n\n");
-  printf("#ifdef CONFIG_DEV_CONSOLE\n");
+  printf("#if defined(CONFIG_DEV_CONSOLE) || defined(CONFIG_CDCACM_CONSOLE) || \\\n");
+  printf("    defined(CONFIG_PL2303_CONSOLE)\n");
   printf("# if CONFIG_NFILE_DESCRIPTORS < 3\n");
   printf("#   undef CONFIG_NFILE_DESCRIPTORS\n");
   printf("#   define CONFIG_NFILE_DESCRIPTORS 3\n");
@@ -145,12 +151,10 @@ int main(int argc, char **argv, char **envp)
   printf("#  undef CONFIG_NFILE_STREAMS\n");
   printf("#  define CONFIG_NFILE_STREAMS 3\n");
   printf("# endif\n\n");
-  printf("/* If no console is selected, then disable all console devices */\n\n");
+  printf("/* If no console is selected, then disable all builtin console devices */\n\n");
   printf("#else\n");
   printf("#  undef CONFIG_DEV_LOWCONSOLE\n");
   printf("#  undef CONFIG_RAMLOG_CONSOLE\n");
-  printf("#  undef CONFIG_CDCACM_CONSOLE\n");
-  printf("#  undef CONFIG_PL2303_CONSOLE\n");
   printf("#endif\n\n");
   printf("/* If priority inheritance is disabled, then do not allocate any\n");
   printf(" * associated resources.\n");