diff --git a/arch/riscv/include/asm/mmiowb.h b/arch/riscv/include/asm/mmiowb.h
index bb4091ff4a21..0b2333e71fdc 100644
--- a/arch/riscv/include/asm/mmiowb.h
+++ b/arch/riscv/include/asm/mmiowb.h
@@ -9,6 +9,7 @@
  */
 #define mmiowb()	__asm__ __volatile__ ("fence o,w" : : : "memory");
 
+#include <linux/smp.h>
 #include <asm-generic/mmiowb.h>
 
 #endif	/* _ASM_RISCV_MMIOWB_H */