Hi Hans, On Wed, 5 Sep 2018 at 19:23, Hans de Goede <hdego...@redhat.com> wrote: > Under Fedora 29 (xserver-1.20) the transition from GDM to > the GNOME3 session is no longer smooth, it seems that the > screen is cleared to black when the Xserver starts instead > of inheriting the framebuffer contents from GDM as before. > > Changing the DDX driver from modesetting to intel fixes this, > I think this may be caused by the new atomic support in the > modesetting driver.
It's caused by support for modifiers: this allows Mesa to use a multi-planar framebuffer (auxiliary compression plane), which the new X server can't then read back from because drmModeGetFB only supports a single plane. I've written up the patches to do that[0], but last time I tried to respin the current mainline was broken and didn't actually boot. I've actually just picked that up this week and am planning to send a new series out tomorrow. [0]: https://lists.freedesktop.org/archives/xorg-devel/2018-March/056363.html Cheers, Daniel _______________________________________________ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: https://lists.x.org/mailman/listinfo/xorg-devel
