diff --git a/package/iperf/Config.in b/package/iperf/Config.in
index c4c25b359d..c284bfd1be 100644
--- a/package/iperf/Config.in
+++ b/package/iperf/Config.in
@@ -1,6 +1,8 @@
 config BR2_PACKAGE_IPERF
 	bool "iperf"
 	depends on BR2_INSTALL_LIBSTDCPP
+	# uses fork()
+	depends on BR2_USE_MMU
 	help
 	  Internet Protocol bandwidth measuring tool for measuring
 	  TCP/UDP performance.