diff --git a/Makefile b/Makefile
index 6f7c971..0de872e 100644
--- a/Makefile
+++ b/Makefile
@@ -115,7 +115,7 @@ qrap: $(QRAP_SRCS) passt.h
 
 valgrind: EXTRA_SYSCALLS="rt_sigprocmask rt_sigtimedwait rt_sigaction \
 			  getpid gettid kill clock_gettime mmap munmap open \
-			  unlink gettimeofday"
+			  unlink gettimeofday futex"
 valgrind: CFLAGS:=-g -O0 $(filter-out -O%,$(CFLAGS))
 valgrind: all