diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index c3eefa126e3b..557a47829d03 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -109,6 +109,8 @@ struct kobject *efi_kobj;
 /*
  * Let's not leave out systab information that snuck into
  * the efivars driver
+ * Note, do not add more fields in systab sysfs file as it breaks sysfs
+ * one value per file rule!
  */
 static ssize_t systab_show(struct kobject *kobj,
 			   struct kobj_attribute *attr, char *buf)