Comment 1 for bug 319210

Could someone test this patch?

diff --git a/hw/xfree86/modes/xf86Crtc.c b/hw/xfree86/modes/xf86Crtc.c
index b972974..f4b04d8 100644
--- a/hw/xfree86/modes/xf86Crtc.c
+++ b/hw/xfree86/modes/xf86Crtc.c
@@ -2940,22 +2940,29 @@ xf86_crtc_clip_video_helper(ScrnInfoPtr pScrn,
 xf86_crtc_notify_proc_ptr
 xf86_wrap_crtc_notify (ScreenPtr screen, xf86_crtc_notify_proc_ptr new)
 {
- ScrnInfoPtr scrn = xf86Screens[screen->myNum];
- xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
- xf86_crtc_notify_proc_ptr old;
-
- old = config->xf86_crtc_notify;
- config->xf86_crtc_notify = new;
- return old;
+ if (xf86CrtcConfigPrivateIndex != -1)
+ {
+ ScrnInfoPtr scrn = xf86Screens[screen->myNum];
+ xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
+ xf86_crtc_notify_proc_ptr old;
+
+ old = config->xf86_crtc_notify;
+ config->xf86_crtc_notify = new;
+ return old;
+ }
+ return NULL;
 }

 void
 xf86_unwrap_crtc_notify(ScreenPtr screen, xf86_crtc_notify_proc_ptr old)
 {
- ScrnInfoPtr scrn = xf86Screens[screen->myNum];
- xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
-
- config->xf86_crtc_notify = old;
+ if (xf86CrtcConfigPrivateIndex != -1)
+ {
+ ScrnInfoPtr scrn = xf86Screens[screen->myNum];
+ xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
+
+ config->xf86_crtc_notify = old;
+ }
 }

 void