diff --git a/sys/conf/kern.mk b/sys/conf/kern.mk
index e86ffb684f9..af7b1589c5c 100644
--- a/sys/conf/kern.mk
+++ b/sys/conf/kern.mk
@@ -166,7 +166,7 @@ INLINE_LIMIT?=	8000
 # code model as "medium" and "medany" respectively.
 #
 .if ${MACHINE_CPUARCH} == "riscv"
-CFLAGS+=	-march=rv64imafdch
+CFLAGS+=	-march=rv64imafdch_zifencei
 CFLAGS+=	-mabi=lp64
 CFLAGS.clang+=	-mcmodel=medium
 CFLAGS.gcc+=	-mcmodel=medany