diff --git a/CMakeLists.txt b/CMakeLists.txt
index 745cef713..2e890aabf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -327,7 +327,7 @@ set(PACKAGE "libwebsockets")
 set(CPACK_PACKAGE_NAME "${PACKAGE}")
 set(CPACK_PACKAGE_VERSION_MAJOR "4")
 set(CPACK_PACKAGE_VERSION_MINOR "0")
-set(CPACK_PACKAGE_VERSION_PATCH "16")
+set(CPACK_PACKAGE_VERSION_PATCH "17")
 set(CPACK_PACKAGE_RELEASE 1)
 set(CPACK_GENERATOR "RPM")
 set(CPACK_PACKAGE_VERSION "${CPACK_PACKAGE_VERSION_MAJOR}.${CPACK_PACKAGE_VERSION_MINOR}.${CPACK_PACKAGE_VERSION_PATCH}")
diff --git a/lib/event-libs/libevent/libevent.c b/lib/event-libs/libevent/libevent.c
index f64a0f9d1..6475d1279 100644
--- a/lib/event-libs/libevent/libevent.c
+++ b/lib/event-libs/libevent/libevent.c
@@ -197,6 +197,7 @@ elops_init_pt_event(struct lws_context *context, void *_loop, int tsi)
 					(EV_READ | EV_PERSIST), lws_event_cb,
 					&vh->lserv_wsi->w_read);
 			event_add(vh->lserv_wsi->w_read.event.watcher, NULL);
+			vh->lserv_wsi->w_read.event.set = 1;
 		}
 		vh = vh->vhost_next;
 	}
@@ -274,17 +275,25 @@ elops_io_event(struct lws *wsi, int flags)
 	       (flags & (LWS_EV_READ | LWS_EV_WRITE)));
 
 	if (flags & LWS_EV_START) {
-		if (flags & LWS_EV_WRITE)
+		if ((flags & LWS_EV_WRITE) && !wsi->w_write.event.set) {
 			event_add(wsi->w_write.event.watcher, NULL);
+			wsi->w_write.event.set = 1;
+		}
 
-		if (flags & LWS_EV_READ)
+		if ((flags & LWS_EV_READ) && !wsi->w_read.event.set) {
 			event_add(wsi->w_read.event.watcher, NULL);
+			wsi->w_read.event.set = 1;
+		}
 	} else {
-		if (flags & LWS_EV_WRITE)
+		if ((flags & LWS_EV_WRITE) && wsi->w_write.event.set) {
 			event_del(wsi->w_write.event.watcher);
+			wsi->w_write.event.set = 0;
+		}
 
-		if (flags & LWS_EV_READ)
+		if ((flags & LWS_EV_READ) && wsi->w_read.event.set) {
 			event_del(wsi->w_read.event.watcher);
+			wsi->w_read.event.set = 0;
+		}
 	}
 }
 
diff --git a/lib/event-libs/libevent/private-lib-event-libs-libevent.h b/lib/event-libs/libevent/private-lib-event-libs-libevent.h
index 6d0029548..9bc8e6841 100644
--- a/lib/event-libs/libevent/private-lib-event-libs-libevent.h
+++ b/lib/event-libs/libevent/private-lib-event-libs-libevent.h
@@ -32,6 +32,7 @@ struct lws_pt_eventlibs_libevent {
 
 struct lws_io_watcher_libevent {
 	struct event *watcher;
+	char		set;
 };
 
 struct lws_signal_watcher_libevent {