Accepting request 917405 from home:xiaoguang_wang:branches:GNOME:Factory

- Add gdm-add-runtime-option-to-disable-starting-X-server-as-u.patch:
  Support to start X under root instead of regular user.
  (bnc#1188912 jsc#SLE-17880).
- Update X11-displaymanager-gdm file.

OBS-URL: https://build.opensuse.org/request/show/917405
OBS-URL: https://build.opensuse.org/package/show/GNOME:Factory/gdm?expand=0&rev=482

X11-displaymanager-gdm

@@ -4,6 +4,16 @@ gdm_vars() {
             RELOADSIGNAL="-USR1"
             DISPLAYMANAGER=/usr/sbin/gdm
             PIDFILE=/run/gdm/gdm.pid
+
+            # let gdm run the Xserver as root if access to /dev/fb*
+            # is required (bsc#1075805)
+            # The GDM_DISABLE_USER_DISPLAY_SERVER variable is added by patch
+            # gdm-add-runtime-option-to-disable-starting-X-server-as-u.patch
+            if [ ! -c /dev/dri/card0 -a \
+                 ! -c /dev/nvidiactl ]; then
+                export GDM_DISABLE_USER_DISPLAY_SERVER=1
+            fi
+
             return 0 ;;
        *) return 1 ;;
     esac