Merge remote-tracking branch 'remotes/kraxel/tags/vga-20180507-pull-request' into staging

qxl: fix local renderer crash

# gpg: Signature made Mon 07 May 2018 10:52:09 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/vga-20180507-pull-request:
  qxl: fix local renderer crash
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/display/qxl-render.c

@@ -169,7 +169,8 @@ void qxl_render_update(PCIQXLDevice *qxl)
 
     qemu_mutex_lock(&qxl->ssd.lock);
 
-    if (!runstate_is_running() || !qxl->guest_primary.commands) {
+    if (!runstate_is_running() || !qxl->guest_primary.commands ||
+        qxl->mode == QXL_MODE_UNDEFINED) {
         qxl_render_update_area_unlocked(qxl);
         qemu_mutex_unlock(&qxl->ssd.lock);
         return;