On Wednesday, July 19th, 2023 at 03:42, Zack Rusin zack@kde.org wrote:
From: Zack Rusin zackr@vmware.com
Cursor planes on virtualized drivers have special meaning and require that the clients handle them in specific ways, e.g. the cursor plane should react to the mouse movement the way a mouse cursor would be expected to and the client is required to set hotspot properties on it in order for the mouse events to be routed correctly.
This breaks the contract as specified by the "universal planes". Fix it by disabling the cursor planes on virtualized drivers while adding a foundation on top of which it's possible to special case mouse cursor planes for clients that want it.
Disabling the cursor planes makes some kms compositors which were broken, e.g. Weston, fallback to software cursor which works fine or at least better than currently while having no effect on others, e.g. gnome-shell or kwin, which put virtualized drivers on a deny-list when running in atomic context to make them fallback to legacy kms and avoid this issue.
Signed-off-by: Zack Rusin zackr@vmware.com Fixes: 681e7ec73044 ("drm: Allow userspace to ask for universal plane list (v2)") Cc: stable@vger.kernel.org # v5.4+ Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Maxime Ripard mripard@kernel.org Cc: Thomas Zimmermann tzimmermann@suse.de Cc: David Airlie airlied@linux.ie Cc: Daniel Vetter daniel@ffwll.ch Cc: Dave Airlie airlied@redhat.com Cc: Gerd Hoffmann kraxel@redhat.com Cc: Hans de Goede hdegoede@redhat.com Cc: Gurchetan Singh gurchetansingh@chromium.org Cc: Chia-I Wu olvaffe@gmail.com Cc: dri-devel@lists.freedesktop.org Cc: virtualization@lists.linux-foundation.org Cc: spice-devel@lists.freedesktop.org Acked-by: Pekka Paalanen pekka.paalanen@collabora.com Reviewed-by: Javier Martinez Canillas javierm@redhat.com
Nit: I think it would be better to reflect the name of the DRM client cap in the supports_virtualized_cursor_plane field.
Regardless:
Reviewed-by: Simon Ser contact@emersion.fr