--- zzzz-none-000/linux-3.10.107/include/linux/cdev.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/include/linux/cdev.h	2021-02-04 17:41:59.000000000 +0000
@@ -30,6 +30,4 @@
 
 void cd_forget(struct inode *);
 
-extern struct backing_dev_info directly_mappable_cdev_bdi;
-
 #endif