--- zzzz-none-000/linux-4.4.271/arch/arm/include/asm/system_misc.h	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/arch/arm/include/asm/system_misc.h	2023-04-19 10:22:27.000000000 +0000
@@ -36,6 +36,7 @@
 #define UDBG_BUS	(1 << 4)
 
 extern unsigned int user_debug;
+extern char* (*arch_read_hardware_id)(void);
 
 #endif /* !__ASSEMBLY__ */