Cosmic Black Screen: Mesa Drivers & Fedora 42 Troubleshoot

by Pedro Alvarez 59 views

Hey everyone,

I recently encountered a frustrating issue with my Cosmic desktop environment on Fedora 42 after installing the mesa-freeworld drivers. After the installation and a reboot, I was greeted with a black screen after logging in, preventing the session from starting. Luckily, I had a Btrfs snapshot to restore my system to its previous state. I wanted to share my experience, the error logs, and hopefully, find a solution or workaround with your help. Let's dive into the mesa-freeworld drivers issue and see what we can figure out together!

The Problem: Black Screen After Installing Mesa-Freeworld Drivers

After several months of smooth sailing with Cosmic, I decided to install the mesa-freeworld drivers on my Fedora 42 system. For those unfamiliar, mesa-freeworld drivers often provide more up-to-date or less restrictive versions of the Mesa graphics library, which can be beneficial for gaming and other graphics-intensive applications. I used the following commands to install the drivers:

sudo dnf swap mesa-vdpau-drivers mesa-vdpau-drivers-freeworld
sudo dnf swap mesa-va-drivers mesa-va-drivers-freeworld

These commands essentially replace the standard Mesa video acceleration drivers with their freeworld counterparts. The installation process seemed to go smoothly, but after rebooting, the trouble began. The Cosmic greeter (login screen) loaded without any issues, but after entering my credentials and logging in, I was met with a dreaded black screen. No desktop, no icons, just a blank display. This was a major setback, but thankfully, I had a recent Btrfs snapshot to revert to.

Digging into the Logs: Identifying the Culprit

Before restoring my snapshot, I made sure to grab the system logs to get a better understanding of what went wrong. Logs are a lifesaver in these situations, as they often contain valuable clues about the root cause of the problem. I examined the logs and found several error messages that seemed relevant. Here’s a snippet of the most concerning entries:

ago 07 23:36:00 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:00Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Dark
ago 07 23:36:00 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:00Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Mode
ago 07 23:36:02 Fedora cosmic-comp[1679]: Failed to submit rendering: Failed to submit result for display

                                          Caused by:
                                              0: The underlying drm surface encountered an error: DRM access error: Page flip commit failed on device `Some("/dev/dri/card1")` (Permission denied (os error 13))
                                              1: DRM access error: Page flip commit failed on device `Some("/dev/dri/card1")` (Permission denied (os error 13))
                                              2: Permission denied (os error 13)
ago 07 23:36:02 Fedora cosmic-comp[1679]: Failed to submit rendering: Rendering failed: The underlying drm surface encountered an error: Device is currently paused, operation rejected
ago 07 23:36:08 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:08Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Dark
ago 07 23:36:08 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:08Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Mode
ago 07 23:36:08 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:08Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTk
ago 07 23:36:24 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:24Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Mode
ago 07 23:36:24 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:24Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTk
ago 07 23:36:24 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:24Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Dark
ago 07 23:36:56 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:56Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTk
ago 07 23:36:56 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:56Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Dark
ago 07 23:36:56 Fedora cosmic-greeter[1793]: [2025-08-07T21:36:56Z ERROR cosmic_config::dbus] Failed to create watcher for com.system76.CosmicTheme.Mode
ago 07 23:37:44 Fedora cosmic-comp[1679]: Failed to destroy old mode property blob: No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-comp[2105]: shortcuts custom config error: GetKey("custom", Os { code: 2, kind: NotFound, message: "No such file or directory" })
ago 07 23:37:49 Fedora cosmic-comp[2105]: tiling exceptions custom config error: GetKey("tiling_exception_custom", Os { code: 2, kind: NotFound, message: "No such file or directory" })
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::pulse] No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::theme] failed to get key 'show_minimize': No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::theme] failed to get key 'show_maximize': No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::theme] failed to get key 'interface_font': No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::theme] failed to get key 'monospace_font': No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::pulse] No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::pulse] No such file or directory (os error 2)
ago 07 23:37:49 Fedora cosmic-session[2035]: [2025-08-07T21:37:49Z ERROR cosmic_settings_daemon::pulse] No such file or directory (os error 2)

Several key errors stand out:

  • cosmic-comp: Failed to submit rendering: Failed to submit result for display
    • This error indicates a problem with the Cosmic compositor failing to render the display. The underlying cause appears to be a DRM (Direct Rendering Manager) access error.
    • DRM access error: Page flip commit failed on device Some("/dev/dri/card1") (Permission denied (os error 13))
    • This specific error suggests a permission issue when trying to flip the display page, which is a crucial step in rendering frames. The Permission denied message is a clear indicator that something is preventing the compositor from accessing the graphics device correctly.
    • Rendering failed: The underlying drm surface encountered an error: Device is currently paused, operation rejected
    • This error might be a consequence of the initial permission issue, where the device is left in a paused state due to the failed page flip.
  • cosmic-greeter: Failed to create watcher for com.system76.CosmicTheme.*
    • These errors suggest issues with the Cosmic greeter failing to monitor changes in the system's theme settings. While these errors might not be the primary cause of the black screen, they could indicate a deeper problem with how Cosmic components are interacting.
  • cosmic-session: No such file or directory (os error 2) and failed to get key ...: No such file or directory (os error 2)
    • These errors, originating from cosmic-session and cosmic_settings_daemon, point to missing configuration files or settings. This could be related to how the mesa-freeworld drivers are interacting with the system's configuration or how Cosmic is attempting to access these settings.

System Information

To provide a clearer picture, here’s some information about my system:

  • cosmic-comp Version: 1.0.0~alpha.7^git20250805.f56ccf0
  • cosmic-greeter Version: 1.0.0~alpha.7^git20250729.b848d52
  • Kernel: Linux Fedora 6.15.9-201.fc42.x86_64 #1 SMP PREEMPT_DYNAMIC Sat Aug 2 11:37:34 UTC 2025 x86_64 GNU/Linux
  • GPU: AMD Radeon RX 6600

I’m running a relatively recent kernel and using an AMD Radeon RX 6600 GPU, which should be well-supported by Mesa. This makes the permission errors even more puzzling.

Possible Causes and Troubleshooting Steps

Based on the error logs and system information, here are a few potential causes and troubleshooting steps we can explore:

  1. DRM Permissions:

    • The Permission denied error in the DRM suggests that the Cosmic compositor might not have the necessary permissions to access the graphics device. This could be due to incorrect udev rules or other permission-related issues.
    • Troubleshooting Steps:
      • Check Udev Rules: Ensure that the udev rules for DRM devices are correctly configured. You can typically find these rules in /usr/lib/udev/rules.d/ or /etc/udev/rules.d/. Look for rules related to DRM or graphics devices.
      • Group Membership: Verify that your user is a member of the video group. This group typically has the necessary permissions to access graphics devices. You can check your group membership using the groups command and add yourself to the video group using sudo usermod -a -G video $USER.
      • SELinux/AppArmor: If you're using SELinux or AppArmor, these security mechanisms might be interfering with the compositor's access to the graphics device. You could try temporarily disabling SELinux (sudo setenforce 0) or AppArmor (sudo systemctl stop apparmor) to see if that resolves the issue. If it does, you'll need to configure SELinux or AppArmor rules to allow the compositor access.

  2. Mesa Driver Issues:

    • While mesa-freeworld drivers often provide improvements, they can sometimes introduce compatibility issues or bugs. It’s possible that the specific version of the drivers I installed has a problem with the Cosmic compositor or my specific hardware configuration.
    • Troubleshooting Steps:
      • Downgrade Mesa Drivers: Try downgrading to a previous version of the Mesa drivers to see if that resolves the issue. You can use dnf history to find the transaction ID of the driver installation and then use sudo dnf downgrade mesa-*-$VERSION to downgrade.
      • Try Different Mesa Flavors: There might be different flavors of Mesa drivers available in your repository (e.g., the standard Mesa drivers). Try switching back to the default Mesa drivers to see if that fixes the problem.
      • Check Mesa Configuration: Ensure that your Mesa configuration is correct. You can check environment variables like MESA_GL_VERSION_OVERRIDE and MESA_GLSL_VERSION_OVERRIDE to see if they're causing any conflicts.

  3. Cosmic Compositor Bugs:

    • As Cosmic is still under heavy development, there’s a possibility that the issue is due to a bug in the compositor itself. The error messages related to failing to submit rendering and destroy mode property blob suggest potential problems within the compositor.
    • Troubleshooting Steps:
      • Update Cosmic Components: Ensure that you’re running the latest versions of the Cosmic components. Check for updates using your package manager (sudo dnf update).
      • Report the Bug: If you suspect a bug in the compositor, report it to the Cosmic developers. Provide detailed information about your system, the steps to reproduce the issue, and the error logs.

  4. Configuration File Issues:

    • The errors from cosmic-session and cosmic_settings_daemon about missing files and keys suggest that there might be issues with configuration files. This could be due to the driver installation process or a problem with how Cosmic is handling its settings.
    • Troubleshooting Steps:
      • Check Configuration Files: Look for the missing files mentioned in the logs (e.g., in /etc/cosmic/, /usr/share/cosmic/, or your user’s configuration directory). Ensure that these files exist and have the correct permissions.
      • Reinstall Cosmic Components: Try reinstalling the Cosmic components to ensure that all configuration files are properly installed. You can use your package manager to reinstall the relevant packages.

Restoring from a Btrfs Snapshot: A Temporary Fix

Since I had a Btrfs snapshot, I was able to quickly restore my system to its state before installing the mesa-freeworld drivers. This got me back up and running, but it’s not a permanent solution. Restoring from a snapshot is a great way to recover from a failed update or installation, but it doesn't address the underlying issue. I still need to figure out why the mesa-freeworld drivers caused this problem so I can use them in the future.

Next Steps and Call for Help

I’ve outlined the issue, shared my logs, and suggested some potential troubleshooting steps. Now, I’m reaching out to the community for help. Have any of you encountered similar issues with mesa-freeworld drivers on Fedora or other distributions? Do you have any insights into the DRM permission errors or the missing configuration file errors? Any suggestions or advice would be greatly appreciated!

I plan to try the following steps next:

  • Investigate Udev Rules: I’ll start by carefully examining the udev rules related to DRM devices to ensure they are correctly configured.
  • Check Group Membership: I’ll double-check my user’s group membership and ensure I’m part of the video group.
  • Experiment with Mesa Versions: I’ll try downgrading or switching to different versions of the Mesa drivers to see if that makes a difference.

I’ll keep you guys updated on my progress. Let's work together to get this resolved and hopefully help others who might encounter the same problem!

Conclusion

Dealing with a black screen after a driver installation can be incredibly frustrating. By sharing our experiences, analyzing logs, and working through troubleshooting steps, we can often find solutions and improve our systems. The issue with mesa-freeworld drivers and Cosmic on Fedora 42 highlights the complexities of graphics driver compatibility and the importance of having a good backup strategy (like Btrfs snapshots). Let’s keep the discussion going and help each other out!