diff --git a/tools/testing/selftests/vfio/Makefile b/tools/testing/selftests/vfio/Makefile
index 0a4cfd1a6c7e..11a237f889d2 100644
--- a/tools/testing/selftests/vfio/Makefile
+++ b/tools/testing/selftests/vfio/Makefile
@@ -23,6 +23,7 @@ include lib/libvfio.mk
 
 CFLAGS += -I$(top_srcdir)/tools/include
 CFLAGS += -MD
+CFLAGS += -Wall -Werror
 CFLAGS += $(EXTRA_CFLAGS)
 
 LDFLAGS += -pthread