8354289650
This can happen if we've got a GBM driver that is incomplete or buggy for any reason. Currently this includes the Nvidia driver when used as a secondary GPU, and as soon as they fix that it will use the fast path instead. Falling back means we can still use it as a KMS device with all rendering done on the primary GPU instead. Just like a DisplayLink. It's slow, but at least the screens all light up now and you get a usable desktop. Surprisingly it's still a better experience than using Xorg, maybe because we can flip the outputs independently with the native backend. Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/2166, https://gitlab.gnome.org/GNOME/mutter/-/issues/2182, https://launchpad.net/bugs/1959888, https://launchpad.net/bugs/1964037 Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2341>
Mutter
Mutter is a Wayland display server and X11 window manager and compositor library.
When used as a Wayland display server, it runs on top of KMS and libinput. It implements the compositor side of the Wayland core protocol as well as various protocol extensions. It also has functionality related to running X11 applications using Xwayland.
When used on top of Xorg it acts as a X11 window manager and compositing manager.
It contains functionality related to, among other things, window management, window compositing, focus tracking, workspace management, keybindings and monitor configuration.
Internally it uses a fork of Cogl, a hardware acceleration abstraction library used to simplify usage of OpenGL pipelines, as well as a fork af Clutter, a scene graph and user interface toolkit.
Mutter is used by, for example, GNOME Shell, the GNOME core user interface, and by Gala, elementary OS's window manager. It can also be run standalone, using the command "mutter", but just running plain mutter is only intended for debugging purposes.
Contributing
To contribute, open merge requests at https://gitlab.gnome.org/GNOME/mutter.
It can be useful to look at the documentation available at the Wiki.
Coding style and conventions
See HACKING.md.
Git messages
Commit messages should follow the GNOME commit message
guidelines. We require an URL
to either an issue or a merge request in each commit. Try to always prefix
commit subjects with a relevant topic, such as compositor: or
clutter/actor:, and it's always better to write too much in the commit
message body than too little.
Default branch
The default development branch is main. If you still have a local
checkout under the old name, use:
git checkout master
git branch -m master main
git fetch
git branch --unset-upstream
git branch -u origin/main
git symbolic-ref refs/remotes/origin/HEAD refs/remotes/origin/main
License
Mutter is distributed under the terms of the GNU General Public License, version 2 or later. See the COPYING file for detalis.