Hello Daniel,
Thank you for the guidance. I have had a look through the upstream
Mutter git history between 46.0 and HEAD to identify exactly what fixed
this in later versions.
Unfortunately, I couldn't find am isolated commit that explicitly fixes
the EACCES or EBUSY race condition on VMSVGA. The stability in GNOME 47+
appears to be a side-effect of significant architectural refactoring in
the KMS backend that occurred during the 47 development cycle
(specifically August 2024).
The most likely candidates for the fix are the changes to KMS threading
synchronization and deadline timers, specifically:
23f3c17f0 ("kms/impl-device: Use deadline timer for all updates")
996eb4b6a ("kms/impl-device: Handle sync_fd in
meta_kms_impl_device_handle_update")
These commits represent a fundamental change in how the KMS backend
handles update timing and locking (moving to explicit sync fences and
broader deadline timer usage). Backporting these changes to Mutter 46
would require pulling in a complex chain of dependencies and structural
changes, which presents a very high regression risk for a stable LTS
release like 24.04.
Given that the "proper" upstream fix involves a major architectural
rewrite, I believe the Hardware Cursor Stabilization Period patch I
submitted is the safest path forward for Ubuntu 24.04. It is a self-
contained quirk that does not touch the complex KMS threading or
synchronization logic and effectively neutralizes the race condition by
enforcing a safe warmup period (~2.5s) using software cursors, allowing
the driver handover to settle before hardware planes are engaged.
Would you be open to accepting this stabilization patch as a specific
workaround for the 46.x series?
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2089709
Title:
Ubuntu 24.04 sometimes logs in to a black screen if the mouse is moved
during login
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/2089709/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
