Bug 2531653 - COSMIC fails to start from Live ISO: cosmic-comp cannot open /dev/dri/card1 (Device or resource busy) [NEEDINFO]
Summary: COSMIC fails to start from Live ISO: cosmic-comp cannot open /dev/dri/card1 (...
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Fedora
Classification: Fedora
Component: cosmic-comp
Version: 45
Hardware: Unspecified
OS: Linux
unspecified
high
Target Milestone: ---
Assignee: Ryan Brue
QA Contact:
URL:
Whiteboard: https://discussion.fedoraproject.org...
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-09-10 20:47 UTC by Geraldo Simião
Modified: 2026-09-30 07:50 UTC (History)
8 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2026-09-27 00:29:12 UTC
Type: ---
Embargoed:
kparal.oss: needinfo? (geraldo.simiao.kutz)


Attachments (Terms of Use)
1 Srcreenshot from journalctl -r (294.63 KB, image/jpeg)
2026-09-11 01:39 UTC, Geraldo Simião
no flags Details
2 Screenshot from journalctl -r (355.80 KB, image/jpeg)
2026-09-11 01:40 UTC, Geraldo Simião
no flags Details
3 Screenshot from journalctl -r (388.71 KB, image/jpeg)
2026-09-11 01:40 UTC, Geraldo Simião
no flags Details
error log after trying to use the workarround (100.21 KB, image/jpeg)
2026-09-17 05:07 UTC, Geraldo Simião
no flags Details
error log after trying to use the workarround 2 (133.59 KB, image/jpeg)
2026-09-17 05:12 UTC, Geraldo Simião
no flags Details

Description Geraldo Simião 2026-09-10 20:47:06 UTC
The Fedora 45 COSMIC Beta 13 Live ISO fails to start a graphical COSMIC session.

The system boots to a TTY and cosmic-session is started, but cosmic-comp fails when trying to acquire the DRM device /dev/dri/card1. The journal reports:

"Failed to add device /dev/dri/card1: Failed to obtain file descriptor for drm device: /dev/dri/card1"

followed by:
"Failed to open device: Device or resource busy (os error 16)"
and:
"Backend initialized without output"

cosmic-comp then exits and cosmic-session attempts to restart it.

The issue was reproduced in QEMU/KVM with and without graphics acceleration. Another tester also seems to reproduce the issue on physical hardware.

For comparison, Fedora 44 Respin (2026-09-01) works correctly using the same VM configuration.

Reproducible: Always

Steps to Reproduce:
1. Boot the Fedora 45 COSMIC Beta 13 Live ISO.
2. Wait for the system to finish booting.
Actual Results:
The Live session does not reach the COSMIC desktop and instead remains at a TTY login prompt.

Expected Results:
The Fedora 45 COSMIC Live session should complete the boot process and automatically start a fully functional COSMIC graphical desktop session, without requiring the user to log in manually or start the graphical session from a TTY.

Additional Information:
Test environment:

Static hostname: localhost-live
Icon name: computer-vm
Chassis: vm
Virtualization: kvm
Operating System: Fedora Linux 45 (COSMIC Prerelease)
CPE OS Name: cpe:/o:fedoraproject:fedora:45
Kernel: Linux 7.2.0-61.fc45.x86_64
Architecture: x86-64
Hardware Vendor: QEMU
Hardware Model: Standard PC _Q35 + ICH9, 2009_
Hardware Version: pc-q35-11.1
Firmware Version: edk2-20260812-5.fc45
Firmware Date: Wed 2026-08-12

The VM has graphics acceleration enabled.

Relevant journal entries (journalctl -r):

Sep 10 19:36:45 localhost-live cosmic-session[1977]: Starting process 'COSMIC_SESSION_SOCK=12 cosmic-comp'
Sep 10 19:36:47 localhost-live cosmic-comp[2199]: error loading system dark theme
Sep 10 19:36:47 localhost-live cosmic-comp[2199]: shortcuts custom config error: GetKey("custom"), Os { code: 2, kind: NotFound, message: "No such file or directory" }
Sep 10 19:36:49 localhost-live cosmic-comp[2199]: Failed to add device /dev/dri/card1: Failed to obtain file descriptor for drm device: /dev/dri/card1

Caused by:
Failed to open device: Device or resource busy (os error 16)

Sep 10 19:36:49 localhost-live cosmic-comp[2199]: Error occured in main(): Backend initialized without output
Sep 10 19:36:49 localhost-live cosmic-session[1977]: cosmic-comp exited with error code 1
Sep 10 19:36:59 localhost-live cosmic-session[1977]: restarted process 'COSMIC_SESSION_SOCK=12 cosmic-comp', now at 1 restarts
Sep 10 19:36:59 localhost-live cosmic-session[1977]: sleeping for 2ms before restarting process cosmic-comp (restart 0)
Sep 10 19:36:59 localhost-live cosmic-session[1977]: draining stdin receiver before restarting process
Sep 10 19:37:01 localhost-live cosmic-session[1977]: cosmic-comp exited with error code 137

Comment 2 Geraldo Simião 2026-09-11 01:39:29 UTC
Created attachment 2157472 [details]
1 Srcreenshot from journalctl -r

Comment 3 Geraldo Simião 2026-09-11 01:40:06 UTC
Created attachment 2157473 [details]
2 Screenshot from journalctl -r

Comment 4 Geraldo Simião 2026-09-11 01:40:35 UTC
Created attachment 2157474 [details]
3 Screenshot from journalctl -r

Comment 5 Efraim Kaov 2026-09-11 09:09:08 UTC
I can confirm that F45 Beta 1.3 Cosmic indeed doesn’t work.

I installed Cosmic DE using the netinst ISO just to confirm what I suspected. The problem seems to be that start-cosmic cannot be launched from the console when using kmscon.

Removing kmscon and enabling getty@.service makes it possible to launch start-cosmic successfully.

Comment 6 Jaroslav Groman 2026-09-11 14:15:02 UTC
Workaround for COSMIC Live image courtesy of GPT-5.6 Terra:

- At the login prompt login as liveuser with no password
- Run: sudo systemd-run --unit=cosmic-kmscon-test --collect /bin/sh -c 'systemctl stop kmsconvt; systemctl restart cosmic-greeter.service'

Apparently one possible fix would be cosmic-greeter.service declaring Conflicts also with kmscon:

# cosmic-greeter.service
[Unit]
Conflicts=kmsconvt getty
After=kmsconvt getty

Comment 7 Kamil Páral (Red Hat) 2026-09-15 07:01:59 UTC
Common issue documentation:
https://discussion.fedoraproject.org/t/common-issue/201696

Comment 8 Geraldo Simião 2026-09-17 05:07:38 UTC
Created attachment 2157946 [details]
error log after trying to use the workarround

I used the same cosmic spin iso (beta 1.3) and tried to apply the workarround but it dindn't work.

Comment 9 Geraldo Simião 2026-09-17 05:12:46 UTC
Created attachment 2157947 [details]
error log after trying to use the workarround 2

I see that I have a typo at the first try. I corrected it but still don't managed to work.

Comment 10 Kamil Páral (Red Hat) 2026-09-17 06:55:32 UTC
Geraldo, you need to use simple quotes, not backticks. Please try with those.

Comment 11 Jocelyn Falempe 2026-09-17 20:47:39 UTC
I just submitted a PR upstream:

https://github.com/pop-os/cosmic-greeter/pull/546

We should backport it to the rpm package.

Comment 12 Jocelyn Falempe 2026-09-18 12:05:50 UTC
And here is the PR for the Fedora package:

https://src.fedoraproject.org/rpms/cosmic-greeter/pull-request/2

Comment 13 Fedora Update System 2026-09-18 20:48:12 UTC
FEDORA-2026-3664f42714 (cosmic-greeter-1.8.0-3.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-3664f42714

Comment 14 Fedora Update System 2026-09-18 20:48:13 UTC
FEDORA-2026-ca2380fb28 (cosmic-greeter-1.8.0-3.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-ca2380fb28

Comment 15 Fedora Update System 2026-09-19 01:40:30 UTC
FEDORA-2026-0a3adea698 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-0a3adea698`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-0a3adea698

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 16 Fedora Update System 2026-09-19 02:19:22 UTC
FEDORA-2026-ca2380fb28 has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-ca2380fb28`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-ca2380fb28

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 17 Fedora Update System 2026-09-19 02:23:08 UTC
FEDORA-2026-3664f42714 has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-3664f42714`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-3664f42714

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 18 Fedora Update System 2026-09-27 00:29:12 UTC
FEDORA-2026-0a3adea698 (cosmic-greeter-1.8.0-3.fc45) has been pushed to the Fedora 45 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 19 Fedora Update System 2026-09-27 00:57:26 UTC
FEDORA-2026-ca2380fb28 (cosmic-greeter-1.8.0-3.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 20 Fedora Update System 2026-09-27 01:12:19 UTC
FEDORA-2026-3664f42714 (cosmic-greeter-1.8.0-3.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 21 Kamil Paral (Fedora Quality) 2026-09-30 07:49:58 UTC
Geraldo, can you please verify whether this was indeed fixed? Thanks a lot!


Note You need to log in before you can comment on or make changes to this bug.