--- zzzz-none-000/linux-4.4.60/arch/arm64/include/asm/smp_plat.h	2017-04-08 07:53:53.000000000 +0000
+++ dragonfly-4020-701/linux-4.4.60/arch/arm64/include/asm/smp_plat.h	2018-11-08 13:36:17.000000000 +0000
@@ -36,6 +36,8 @@
 	return 1 << mpidr_hash.bits;
 }
 
+extern void secondary_startup(void);
+
 /*
  * Logical CPU mapping.
  */