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Jonas Ådahl 8bc375005c kms/connector: Don't query the kernel twice when updating
On hotplug, the events we receive from the kernel are async, and
connectors in the kernel come and go as they please. In practice, this
means that calling drmModeGetConnector() twice more or less directly
after each other, there is no guarantee that the latter call will return
anything if the former did.

When updating the connector in response to hotplugs, we'd first update
the list of existing connectors, and following that, query each and
every one again for their current state, to update our internal
representation; only the former handled drmModeGetConnector() returning
NULL, meaning if unlucky, we'd end up doing a null pointer dereference
when trying to update the state.

Handle this by querying the kernel for the current connector state only
once per connector, updating the list of connectors and their
corresponding state at the same time.

Fixes the following crash:

    #0 meta_kms_connector_read_state at ../src/backends/native/meta-kms-connector.c:684
    #1 meta_kms_connector_update_state at ../src/backends/native/meta-kms-connector.c:767
    #2 meta_kms_impl_device_update_states at ../src/backends/native/meta-kms-impl-device.c:916
    #3 meta_kms_device_update_states_in_impl at ../src/backends/native/meta-kms-device.c:267
    #4 meta_kms_update_states_in_impl at ../src/backends/native/meta-kms.c:604
    #5 update_states_in_impl at ../src/backends/native/meta-kms.c:620
    #6 meta_kms_run_impl_task_sync at ../src/backends/native/meta-kms.c:435
    #7 meta_kms_update_states_sync at ../src/backends/native/meta-kms.c:641
    #8 handle_hotplug_event at ../src/backends/native/meta-kms.c:651
    #9 on_udev_hotplug at ../src/backends/native/meta-kms.c:668

Related: https://bugzilla.redhat.com/show_bug.cgi?id=2131269
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2709>
2022-11-24 16:18:22 +00:00
.gitlab/issue_templates gitlab: Add missing < in markdown comment tag 2020-02-14 03:10:28 +00:00
.gitlab-ci ci: Only launch a single mocked D-Bus environment for all tests 2022-11-01 21:04:21 +00:00
clutter clutter/stage: Always queue events in _clutter_stage_queue_event() 2022-11-22 20:31:42 +00:00
cogl g-i: Drop unneeded since/stability annotations 2022-11-22 13:32:52 +01:00
data data/udev: Don't disable KMS modifiers on newer i915 systems 2022-11-04 18:23:15 +00:00
doc docs/cogl-pango: Update urlmap 2022-11-22 13:32:52 +01:00
meson build: Replace custom post-install script 2022-11-19 02:21:05 +01:00
po Update Slovak translation 2022-11-22 22:15:02 +00:00
src kms/connector: Don't query the kernel twice when updating 2022-11-24 16:18:22 +00:00
subprojects build: bump ABI to sysprof-capture-4 2020-07-28 11:13:30 -07:00
tools tools/get-state: Round refresh rates to three decimal places 2022-08-19 15:28:56 +00:00
.gitignore wayland: Remove Gtk primary selection protocol 2022-05-18 20:15:08 +00:00
.gitlab-ci.yml ci: Only launch a single mocked D-Bus environment for all tests 2022-11-01 21:04:21 +00:00
check-style.py ci: Avoid deadlock while reading uncrustify output 2021-08-23 17:40:43 +02:00
config.h.meson core: Make sound player feature optional 2022-09-02 08:04:31 +00:00
COPYING Updated obsolete FSF postal address in COPYING 2014-01-12 08:44:30 +07:00
HACKING.md docs: Update coding style link 2021-11-09 19:52:14 +01:00
meson_options.txt core: Make sound player feature optional 2022-09-02 08:04:31 +00:00
meson.build build: Replace custom post-install script 2022-11-19 02:21:05 +01:00
mutter.doap mutter.doap: Add marge-bot as a maintainer 2020-11-16 11:59:45 +01:00
NEWS Bump version to 43.1 2022-11-03 16:19:36 +01:00
README.md readme: Fix typo 2022-07-29 16:52:12 -04:00

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 of 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.

The API documentation is available at:

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.