GNOME Bugzilla – Bug 657431
shell forces fallback mode for external monitor if already plugged in at boot time despite applied one-screen setup in gnome settings
Last modified: 2016-03-02 11:38:53 UTC
I use an Asus Eee laptop and sometimes work with an external 1680x1050 monitor. If I plug in the monitor at boot time already, the login will work fine but as soon as gnome-shell is supposed to start, Gnome 3 forces me into fallback mode. If I plug in the monitor while I'm logged in and gnome-shell is running, it works fine (the monitor is recognised, shell is transferred to external screen and I can work fine with it). Since I often have my laptop in stationary mode with lid closed and external keyboard/mouse, this is quite odd since I have to boot without the external screen closed and use the internal one which isn't exactly easily reachable in that configuration and then login before plugging in the monitor again. Gnome version: 3.0.1 Memory: 994.1MB Processor: Intel® Atom™ CPU N270 @ 1.60GHz × 2 Graphics: Intel® 945GME OS type: 32-bit Disk: 19.6 GB uname -a: Linux jth 2.6.40.3-0.fc15.i686 #1 SMP Tue Aug 16 04:24:09 UTC 2011 i686 i686 i386 GNU/Linux yum info xorg-x11-drv-intel: Loaded plugins: auto-update-debuginfo, langpacks, presto, refresh-packagekit Installed Packages Name : xorg-x11-drv-intel Arch : i686 Version : 2.15.0 Release : 5.fc15 Size : 786 k Repo : installed From repo : updates Summary : Xorg X11 Intel video driver URL : http://www.x.org License : MIT Description : X.Org X11 Intel video driver.
So, this is probably because the X server default configuration (which is applied when it starts) is to expand the frame buffer to all monitors[1]. On your setup this yields an horizontal resolution which is greater than the maximum texture size for you GPU (2048) and thus gnome-shell won't start. When you're already logged in the default X behavior doesn't apply, it's gnome-settings-daemon who setups the xrandr layout and it's probably configured to disable the internal monitor and leave only the external. [1] I think this behavior is Fedora specific, the upstream X server clones by default IIRC *** This bug has been marked as a duplicate of bug 645087 ***
gdm does indeed cover both monitors. But the odd behaviour is: The fallback mode actually does *not* cover both screens. So I don't see why exactly gnome-shell couldn't run in that configuration. Therefore this seems to be a different bug, as it doesn't actually have a two screen setup in fallback mode either (which #645087 is about). It rather seems to be some sort of order problem that the gnome-settings-daemon changes the setup to one monitor *after* the shell tries to start, so the shell doesn't start although it perfectly could (as opposed to an actual two screen setup as in #645087).
Well actually now as I am thinking of it, fixing #645087 should also fix this one regardless. Still, it seems to be a different issue to me and *could* be fixed separately I assume (by changing the startup order).
*** Bug 674132 has been marked as a duplicate of this bug. ***
Sorry for that double-post... Did someone actually look into fixing this? It is really annoying to unplug the external screen at boot, open up the closed internal screen, logging in there, closing the internal screen, plugging back the monitor and only then get a usable gnome 3.
About "[1] I think this behavior is Fedora specific, the upstream X server clones by default IIRC": Does this mean this should be reported downstream at Fedora instead?
*** This bug has been marked as a duplicate of bug 646280 ***