diff --git a/src/libcamera/event_dispatcher_poll.cpp b/src/libcamera/event_dispatcher_poll.cpp
index a497a7fe9..69edfcbf2 100644
--- a/src/libcamera/event_dispatcher_poll.cpp
+++ b/src/libcamera/event_dispatcher_poll.cpp
@@ -173,7 +173,7 @@ short EventDispatcherPoll::EventNotifierSetPoll::events() const
 	return events;
 }
 
-void EventDispatcherPoll::processNotifiers(std::vector<struct pollfd> &pollfds)
+void EventDispatcherPoll::processNotifiers(const std::vector<struct pollfd> &pollfds)
 {
 	static const struct {
 		EventNotifier::Type type;
diff --git a/src/libcamera/include/event_dispatcher_poll.h b/src/libcamera/include/event_dispatcher_poll.h
index 30fd58506..a41926e11 100644
--- a/src/libcamera/include/event_dispatcher_poll.h
+++ b/src/libcamera/include/event_dispatcher_poll.h
@@ -41,7 +41,7 @@ private:
 	std::map<int, EventNotifierSetPoll> notifiers_;
 	std::list<Timer *> timers_;
 
-	void processNotifiers(std::vector<struct pollfd> &pollfds);
+	void processNotifiers(const std::vector<struct pollfd> &pollfds);
 	void processTimers();
 };