Bug 2356047

Summary: vncviewer (tigervnc-1.15) -FullScreen on localhost loops when there is no window manager
Product: [Fedora] Fedora Reporter: Francis Montagnac <francis.montagnac>
Component: tigervncAssignee: Jan Grulich <jgrulich>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 41CC: jgrulich
Target Milestone: ---Keywords: Desktop, Regression, Upgrades
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: tigervnc-1.15.0-5.fc42 tigervnc-1.15.0-5.fc41 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2025-04-17 19:00:01 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Francis Montagnac 2025-03-30 07:44:04 UTC
When calling "vncviewer -FullScreen localhost:N" in a context without a window manager,
the screen becomes white and flashes infinitely until one kills vncviewer.

Increasing the logs shows that vncviewer is looping on: Config: Set FullScreen(Bool) to on

Reproducible: Always

Steps to Reproduce:
1. Start Xvnc on :2

  Xvnc -desktop test -SecurityTypes None -nolisten tcp -Log *:stderr:30 :2 2> /tmp/Xvnc.log &

2. Start an X session without a DM

  startx /bin/xterm -ls -- :1

3. Call vncviewer from the xterm in this X session

  vncviewer -FullScreen -Log *:stderr:100 localhost:2 2> /tmp/vncviewer-1.15-no-wm.log

Hit quickly ^C to stop vncviewer.

The vncviewer log shows infinitely:

 Config:      Set FullScreen(Bool) to on

Actual Results:  
vncviewer fails

Expected Results:  
succeed

A workaround is to call vncviewer with a DesktopSize and let the user switch to FullScreen
afterwards if needed

Comment 1 Francis Montagnac 2025-03-30 07:49:48 UTC
I forgot to say that this does not happen with earlier versions of tigervnc ex: tigervnc-1.14.1-2.fc41

Comment 2 Jan Grulich 2025-03-31 07:47:43 UTC
Can you please forward your issue to Tigervnc upstream?

Upstream tracker: https://github.com/TigerVNC/tigervnc/issues

Comment 3 Francis Montagnac 2025-03-31 08:09:58 UTC
I will do. Thanks for suggesting it.

Comment 4 Francis Montagnac 2025-03-31 09:01:51 UTC
This is done: https://github.com/TigerVNC/tigervnc/issues/1936

Comment 5 Jan Grulich 2025-03-31 09:03:30 UTC
Thank you. I will follow the upstream bug and backport the fix (if any) to Fedora.

Comment 6 Fedora Update System 2025-03-31 13:26:36 UTC
FEDORA-2025-e722a4e0e8 (tigervnc-1.15.0-3.fc41) has been submitted as an update to Fedora 41.
https://bodhi.fedoraproject.org/updates/FEDORA-2025-e722a4e0e8

Comment 7 Fedora Update System 2025-03-31 13:26:37 UTC
FEDORA-2025-4e979b9d95 (tigervnc-1.15.0-3.fc42) has been submitted as an update to Fedora 42.
https://bodhi.fedoraproject.org/updates/FEDORA-2025-4e979b9d95

Comment 8 Francis Montagnac 2025-03-31 14:05:15 UTC
(In reply to Fedora Update System from comment #6)
> FEDORA-2025-e722a4e0e8 (tigervnc-1.15.0-3.fc41) has been submitted as an
> update to Fedora 41.
> https://bodhi.fedoraproject.org/updates/FEDORA-2025-e722a4e0e8

I confirm that this version solves the problem. Thanks a lot.

In addition the log shows:

    PlatformPixelBuffer: Using shared memory XImage
     DesktopWindow: Adjusting window size to avoid accidental full-screen request
     CConn:       Using pixel format depth 24 (32bpp) little-endian rgb888
     Config:      Set FullScreen(Bool) to on
     DesktopWindow: Ignored synthetic focus event cause by grab change

instead of (with tigervnc-1.15.0-2):

    PlatformPixelBuffer: Using shared memory XImage
     CConn:       Using pixel format depth 24 (32bpp) little-endian rgb888
     Config:      Set FullScreen(Bool) to on
     Config:      Set FullScreen(Bool) to on
     Config:      Set FullScreen(Bool) to on
     # infinitely

Comment 9 Fedora Update System 2025-04-01 03:11:18 UTC
FEDORA-2025-e722a4e0e8 has been pushed to the Fedora 41 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2025-e722a4e0e8`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2025-e722a4e0e8

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

Comment 10 Fedora Update System 2025-04-01 03:25:47 UTC
FEDORA-2025-4e979b9d95 has been pushed to the Fedora 42 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2025-4e979b9d95`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2025-4e979b9d95

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

Comment 11 Fedora Update System 2025-04-03 03:42:31 UTC
FEDORA-2025-4e979b9d95 has been pushed to the Fedora 42 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2025-4e979b9d95`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2025-4e979b9d95

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

Comment 12 Fedora Update System 2025-04-09 01:25:19 UTC
FEDORA-2025-e722a4e0e8 has been pushed to the Fedora 41 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2025-e722a4e0e8`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2025-e722a4e0e8

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

Comment 13 Fedora Update System 2025-04-09 02:38:31 UTC
FEDORA-2025-4e979b9d95 has been pushed to the Fedora 42 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2025-4e979b9d95`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2025-4e979b9d95

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

Comment 14 Fedora Update System 2025-04-17 19:00:01 UTC
FEDORA-2025-4e979b9d95 (tigervnc-1.15.0-5.fc42) has been pushed to the Fedora 42 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 15 Fedora Update System 2025-04-24 17:32:56 UTC
FEDORA-2025-e722a4e0e8 (tigervnc-1.15.0-5.fc41) has been pushed to the Fedora 41 stable repository.
If problem still persists, please make note of it in this bug report.