diff --git a/configure.ac b/configure.ac
index 0b72860f61..89a7a9db90 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2223,6 +2223,14 @@ AC_SUBST([prefix])
 
 AC_CONFIG_COMMANDS([sdksyms], [touch hw/xfree86/sdksyms.dep])
 
+if test "x$CONFIG_HAL" = xno && test "x$CONFIG_UDEV" = xno; then
+    AC_WARN([
+             ***********************************************
+             Neither HAL nor udev backend will be enabled.
+             Input device hotplugging will not be available!
+             ***********************************************])
+fi
+
 AC_OUTPUT([
 Makefile
 glx/Makefile