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            <b><a class="bz_bug_link 
          bz_status_NEEDINFO "
   title="NEEDINFO --- - display turns off with intel(0): sna_mode_redisplay: page flipping failed, disabling CRTC:3 (pipe=0)"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=70905#c23">Comment # 23</a>
              on <a class="bz_bug_link 
          bz_status_NEEDINFO "
   title="NEEDINFO --- - display turns off with intel(0): sna_mode_redisplay: page flipping failed, disabling CRTC:3 (pipe=0)"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=70905">bug 70905</a>
              from <span class="vcard"><a class="email" href="mailto:chris@chris-wilson.co.uk" title="Chris Wilson <chris@chris-wilson.co.uk>"> <span class="fn">Chris Wilson</span></a>
</span></b>
        <pre>Ok, but I don't think that assert explains the pageflip failure though. :(

This should fix the assert:

diff --git a/src/sna/sna_display.c b/src/sna/sna_display.c
index 10ee9e4..000d9ab 100644
--- a/src/sna/sna_display.c
+++ b/src/sna/sna_display.c
@@ -4530,7 +4530,17 @@ void sna_mode_redisplay(struct sna *sna)
                return;
        }

-       assert(sna_pixmap(sna->front)->move_to_gpu == NULL);
+       {
+               struct sna_pixmap *priv;
+
+               priv = sna_pixmap(sna->front);
+               assert(priv != NULL);
+
+               if (priv->move_to_gpu)
+                       (void)priv->move_to_gpu(sna, priv, 0);
+
+               assert(priv->move_to_gpu == NULL);
+       }

        for (i = 0; i < config->num_crtc; i++) {
                xf86CrtcPtr crtc = config->crtc[i];</pre>
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