lubuntu groovy; flashing of sddm greeter

[Chris Guiver]

Lubuntu groovy QA-test install on
dell [optiplex] 990 (i7-2600, 16gb, nvidia geforce gt 6600 gt)

On reboot, the login greeter (sddm) screen isn't nice, with areas of the screen flashing white/black/white/black (maybe white & black each second like a ":" might flash on the clock, only the ":" on the clock is static)

likely package at fault should be xserver-xorg-video-nouveau

Photo can be seen at

https://photos.app.goo.gl/SYPytVxtkKBEj9NY8

The
- drop down for session (not selected Lubuntu)
- language drop down (not US flag)
- white/black on login picture (not grey name)

flashes black & white on a cycle...

The top panel items will eventually stop flashing (ie. session & layout) but time or certain actions cause the flashing white then black in cycle to occur again.

** Expected Result

No flashing, its irritating & potentially a problem for some with certain health conditions.

** Not new issue, it's occurred in the past

hp dx6120mt (pentium 4, 3gb, winfast clone of nvidia 7600gt)

I've had this issue before on eoan on hp dx6120 i believe but cannot find bug report. The bug was likely not filed as that box was i386 & support was being dropped when I noticed it so I didn't see any point.

It's not new, and no doubt relates to Nvidia cards, and I'm convinced I've filed this before on dx6120 so if not eoan, disco, but I've not yet found it.

ProblemType: Bug
DistroRelease: Ubuntu 20.10
Package: linux-image-5.8.0-18-generic 5.8.0-18.19
ProcVersionSignature: Ubuntu 5.8.0-18.19-generic 5.8.4
Uname: Linux 5.8.0-18-generic x86_64
ApportVersion: 2.20.11-0ubuntu45
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: guiverc 1095 F.... pulseaudio
 /dev/snd/controlC0: guiverc 1095 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: LXQt
CurrentDmesg: Error: command ['dmesg'] failed with exit code 1: dmesg: read kernel buffer failed: Operation not permitted
Date: Thu Sep 17 11:13:50 2020
InstallationDate: Installed on 2021-09-17 (-365 days ago)
InstallationMedia: Lubuntu 20.10 "Groovy Gorilla" - Alpha amd64 (20200916)
IwConfig:
 lo no wireless extensions.

 eno1 no wireless extensions.
Lsusb:
 Bus 002 Device 003: ID 046d:c534 Logitech, Inc. Unifying Receiver
 Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Dell Inc. OptiPlex 990
ProcFB: 0 nouveaudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.8.0-18-generic root=UUID=c29a66dc-4cfc-4dc1-9fe7-3c9d8a8ab4a1 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-5.8.0-18-generic N/A
 linux-backports-modules-5.8.0-18-generic N/A
 linux-firmware 1.190
RfKill:

SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/05/2017
dmi.bios.release: 4.6
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A20
dmi.board.name: 06D7TR
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 6
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA20:bd05/05/2017:br4.6:svnDellInc.:pnOptiPlex990:pvr01:rvnDellInc.:rn06D7TR:rvrA00:cvnDellInc.:ct6:cvr:
dmi.product.name: OptiPlex 990
dmi.product.version: 01
dmi.sys.vendor: Dell Inc.
---
ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu45
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: guiverc 950 F.... pulseaudio
 /dev/snd/controlC0: guiverc 950 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: LXQt
CurrentDmesg: Error: command ['dmesg'] failed with exit code 1: dmesg: read kernel buffer failed: Operation not permitted
DistroRelease: Ubuntu 20.10
InstallationDate: Installed on 2021-09-17 (-365 days ago)
InstallationMedia: Lubuntu 20.10 "Groovy Gorilla" - Alpha amd64 (20200916)
IwConfig:
 lo no wireless extensions.

 eno1 no wireless extensions.
Lsusb:
 Bus 002 Device 003: ID 046d:c534 Logitech, Inc. Unifying Receiver
 Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Dell Inc. OptiPlex 990
Package: linux (not installed)
ProcFB: 0 nouveaudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.8.0-18-generic root=UUID=c29a66dc-4cfc-4dc1-9fe7-3c9d8a8ab4a1 ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 5.8.0-18.19-generic 5.8.4
RelatedPackageVersions:
 linux-restricted-modules-5.8.0-18-generic N/A
 linux-backports-modules-5.8.0-18-generic N/A
 linux-firmware 1.190
RfKill:

Tags: groovy
Uname: Linux 5.8.0-18-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sudo
_MarkForUpload: True
dmi.bios.date: 05/05/2017
dmi.bios.release: 4.6
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A20
dmi.board.name: 06D7TR
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 6
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA20:bd05/05/2017:br4.6:svnDellInc.:pnOptiPlex990:pvr01:rvnDellInc.:rn06D7TR:rvrA00:cvnDellInc.:ct6:cvr:
dmi.product.name: OptiPlex 990
dmi.product.version: 01
dmi.sys.vendor: Dell Inc.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1895905

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1895905

[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

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[Chris Guiver (guiverc)]

I'll note

https://bugs.launchpad.net/ubuntu/+source/sddm/+bug/1865837
"Lubuntu 20.04 qa-test install; flashing at sddm greeter when mouse at top panel (pre-login)"

which reads very similar, maybe even same cause (similar pattern at least in flashing), but occurs different positions on the screen.

This was not the duplicate I'm hunting for...

[Chris Guiver (guiverc)]

Another QA-test install (groovy) on
dell [optiplex] 990 (i7-2600, 16gb, nvidia geforce gt 6600 gt)
testcase: full disk, encryption, BIOS, no internet

got thru encryption and got to ssdm.

entered random keys into sddm (fingers incorrectly positioned so it'd be incorrect), screen was horrid but it didn't log me in as expected.

I was then UNABLE to see what occurred, backspace didn't work, screen kept shaking/flashing and made no sense as I attempted to correct random keys and enter a password correctly; I tried a couple of times following the display and was unable. this was a somewhat serious flaw today (because of invalid entry first time as with fingers incorrectly placed)

I could successfully login when I shut my eyes & just used the keyboard without following the screen at all, so box is working exactly as expected... but the video issue is a problem with sddm on this box for some reason.

Logged out & played again, at times the DOTS are erased when the line is completely empty, however most of the time it shows dots even after pressing <BACKSPACE> many times (more times than keys hit, ie. <I>x3 followed by <backspace>x4 should be empty field but it may still have 3 or 7 dots???????? It appears inconsistent!??

I'll have to explore it some more

[Chris Guiver (guiverc)]

Lubuntu hirsute install on
dell [optiplex] 990 (i7-2600, 16gb, nvidia geforce gt 6600 gt)

wxl suggested (https://discourse.lubuntu.me/t/login-screen-flashes/1634/14?u=guiverc) exploration of this, so I did a clean install so I can play

It's worse than any groovy install, something may have changed, as the response is different (& worse) .. the whole screen is flashing (except for top panel) [instead of just small portions of the screen]

[Chris Guiver (guiverc)]

I tried each of

sddm-theme-debian-elarun - 'Debian Elarun' Theme for SDDM X11 display manager
sddm-theme-debian-maui - 'Debian Maui' theme for SDDM X11 display manager
sddm-theme-elarun - 'Elarun' Theme for SDDM X11 display manager
sddm-theme-lubuntu - Lubuntu theme for SDDM X11 display manager
sddm-theme-maldives - 'Maldives' theme for SDDM X11 display manager
sddm-theme-maui - 'Maui' theme for SDDM X11 display manager
sddm-theme-maya - 'Maya' theme for SDDM X11 display manager

and it was the same (flashing effect) for each theme (I skipped trying `sddm-theme-breeze` as it was going to pull in a lot of KF5 etc, I can’t see why it would be different, let me know if it’s worth trying)

I added & made default `xdm` and the login flashing disappeared.

This however had the effect of changing the theme used by the panel (I noticed it too on *hp dc7700*). I don’t consider this an issue though; they are easily changed back in *Appearances*. Changes are
– sddm
* qt style - breeze
* lxqt-theme - Lubuntu Arc
– xdm
* qt style - fusion
* lxqt-theme - frost

[Kai-Heng Feng (kaihengfeng)]

Have you tried GDM or LightDM? Do they have the same issue?

[Chris Guiver (guiverc)]

This issue can re-created by booting the Lubuntu daily live (hirsute), logging out and as you go to `sddm` you see the issue. done with today's hirsute daily.

@Kai-Heng Feng (kaihengfeng)

Using the installation done in comment #21-22, I added

- lightdm

no issues discovered, I could login normally and no issues discovered in quick play. I did a few groovy Xubuntu installs on this, it was where I discovered other issues, but I don't recall flashing-issues.

I also noted Kubuntu is available on the list of sessions, so I tried that.. The kubuntu wasn't usable though; the characters on screen icons are missing.. eg. what I think is supposed to be "Computer" showed as "Co pute" one time, next time only the "t" was missing.. Some issues I wonder if missing packages, but there are graphic issues it feels like here.

- gdm3

this doesn't look right. I've taken numerous photos, so I'll upload and paste links, but I'll also find & boot a Ubuntu desktop to compare so I can better describe issues.

Once logged in lubuntu was good just as with lightdm/xdm/sddm (issues if I used kubuntu identical to those experienced with lightdm as greeter)

The issue with gdm3 is not the same, it's NOT flashing, however graphics just don't like as I believe they should (white areas on screen appears to be issue rather than the flashing). More to come..

No

[Chris Guiver (guiverc)]

continuing comment #24 (links to photos)

- gdm3 photos

https://photos.app.goo.gl/koM6HAL4ZDFDTdvc8
https://photos.app.goo.gl/SgBroo8vrMB8Bp6K9
https://photos.app.goo.gl/txdBXNVxii5mHZrZ6
https://photos.app.goo.gl/TVLNm4WFuPQbsTSq6

- logged into plasma (missing character example)

https://photos.app.goo.gl/RWKzMzoqTbCmjPXW7
(didn't take photo of menu; screen was glitchy in operation; flashing black triangles (though they settled down when mouse wasn't being touched, until sddm which flashes time/pattern). The graphic glitches have on the desktop have been reported elsewhere

[Chris Guiver (guiverc)]

Walter/wxl asked me to test `sddm-theme-breeze` I skipped in comment #22, report posted (https://discourse.lubuntu.me/t/login-screen-flashes/1634/17?u=guiverc) days ago now pasted here

---
I added `sddm-theme-breeze` and rebooted, yuk! (I had forgotten to perform the `sudo update-alternatives --config sddm-ubuntu-theme` step but `sddm` had been changed by the additional of a virtual keyboard) making it harder to use.

I've seen this before (*semi-recently with dual screens*) and recalled the on-screen keyboard appearing on secondary display, but it booted with keyboard drawn on black background, on mouse movement etc it would flash between black, on-screen keyboard (using 2/3rds of single display) & background.. *yuk*

If a user watched the display, they'd have trouble being able to login.

`sddm` is still working, if I close my eyes & login as I'd expect it to operate, I'm logged in, but visually it's a mess & unusable on that box.

The behavior is very familiar though, I added `kubuntu-desktop` to my Lubuntu *focal* installs on d755-5 (mentioned 4 messages up, AMD and flashing `sddm`; [lp 1865837](https://bugs.launchpad.net/ubuntu/+source/sddm/+bug/1865837)) and that box has only single display and it had the same behavior if I recall correctly. (*it was also added to hp8200 install which has the two displays*)

Finally I performed the `sudo update-alternatives --config sddm-ubuntu-theme` to make the 'new' breeze default, and on reboot it hung before eventual shutdown...errors?

`sddm` didn't appear again. The GUI session now has a large pointer, which I can move around with the mouse, but nothing more.

I can fix this currently by changing the theme to something else, but with the virtual keyboard appearing on all themes now, they're all rather annoying..

I've taken some photos of messages I see on screen (sddm-greeter & nouveau) but my phone is being annoying (no messages in `dmesg` or `journalctl` which I could easily paste; & `/var/log/sddm.log` is empty). Most messages appear during shutdown which was ultra slow with breeze the default.

Switching to another theme and shutdown returns to normal, messages gone (*just virtual terminal remains which isn't helpful*).

The one message I get on text terminal (with breeze active) is
`[ 120.676863] nouveau 0000:01:00.0: DRM: GPU lockup - switching to software fbcon`
written after the "Optiplex990 login:"

Either a requirement is missing (package error) or we're missing something in config??

-- links to photos
- shutdown messages
https://photos.app.goo.gl/Yf5pK28w4FMUmSi17
https://photos.app.goo.gl/VBvvRrzKMDWjxPjx5
- switching to text terminal; message
https://photos.app.goo.gl/nRJEGJHd45WoenSb8
---

Additional note, the switching-to-text-terminal message (last photo link) I saw once today too, I think when using `gdm3`, but I don't believe I did when using `lightdm`. If this detail is useful, I'd need to re-test to confirm this

[Chris Guiver (guiverc)]

Used box with Kubuntu hirsute daily
dell [optiplex] 990 (i7-2600, 16gb, nvidia geforce gt 6600 gt)

The session there was almost impossible to use (flashing quickly gave me a headache & made me feel queezy). I filed issue under
https://bugs.launchpad.net/ubuntu/+source/kubuntu-meta/+bug/1891408

SDDM didn't give me grief (except if left idle, as the username/password dialog box disappeared the screen flashed badly very briefly, also when you caused it to re-appear).

Could that issue be related to this?

That bug report was until today, filed on i386 box only, but the pictures of that report looked the same.. experience about the same..

[Kai-Heng Feng (kaihengfeng)]

Please file an upstream bug at
https://gitlab.freedesktop.org/drm/nouveau/issues

[Chris Guiver (guiverc)]

filed https://gitlab.freedesktop.org/drm/nouveau/-/issues/20

[Wladimir Mutel (mwg)]

I am affected by this bug (P7P55 LX motherboard, GeForce 7600 video, Lubuntu/LXQt 20.04 x86_64 with sddm)
See also older bug report at lp:1785184

[Piotr (peterq94)]

@guiverc If I will install LightDM this will be works with no issues with LXQt environment? sddm is unusable for me so this is important question.

Or maybe is a way to eliminate Display Manager and log in with terminal and next start LXQt? Can you answer me?

[Chris Guiver (guiverc)]

@piotr (peterq94)
refer comments #22 & #24 on this report.

I've written about this (work-around) on Lubuntu's discourse I believe too (https://discourse.lubuntu.me/t/login-screen-flashes/1634/7 and maybe elsewhere too). I've lost access to the d990 (which wasn't my box) so I can't test further with it.

There are other bugs relating to sddm flashing (non-nvidia graphics) which can likewise be mitigated as this was. Support questions should be directed to support venues; not bug trackers.

[Chris Guiver (guiverc)]

Thank you for reporting this bug to Ubuntu.

Ubuntu 21.04 (hirsute) reached end-of-life on January 20, 2022.
Ubuntu 20.10 (groovy) reached end-of-life on July 22, 2021.

See this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test. If you then find the bug is still present in the newer Ubuntu version, please add a comment here telling us which new version it is in.

(I don't think I still have the box this bug report was filed on, but the video card was not my own so I cannot retest with that card)