Graphic problem after update to 5.5.3

[bdcomp]

Hi,

I just updated my Kubuntu 15.10 64bit (AMD A8-6500T, Mesa) to Plasma 5.5.3 via the Kubuntu Backports PPA.
Old Xsession file been left while asked about replace to the new version.

After reboot - the screen is full with horizontal lines, although everything seems to work.
But - after killing the X by Ctrl-Alt-Backspace and logging in again, with the same user - everything works.

What I tried, without any result:

1. Clearing ~/.cache directory
2. sudo apt-get install -f
3. sudo dpkg --configure -a
4. Rename of Root/usr/share/sddm/scripts Xsession to Xsession.old and Xsession.dpkg-dist to Xsession

Update: A picture of the lines:
http://pasteboard.co/UtIIj1U.jpg

Any suggestion how to auto login like manually after exiting X?

[bdcomp]

A bug report just filled: https://bugs.launchpad.net/ubuntu/+bug/1535763

Please help me assign and subscribe the right developers.

[Teunis]

I have little experience with AMD video but on nVidia and Intel you can also play with the backend for rendering, the options are, GL 3.1, GL 2.0 and XRender.

[bdcomp]

I solved this (after about 14 hours...) by:
sudo ppa-purge ppa:kubuntu-ppa/backports
Now I am again on Plasma 5.4.3
Just needed to install Muon again:
sudo apt-get install muon

Maybe one day I will try again to update via the Backports PPA and replace the Xsession file.

[Gerii]

Same problem here on AMD R9 290 and stock open source drivers. With XRender it currently seems to work.

[Guest]

Do you mean something like this? Then I've noticed it too. The problem goes away when switching to XRender.

[bdcomp]

[ATTACH=CONFIG]6424[/ATTACH]

Do you mean something like this? Then I've noticed it too. The problem goes away when switching to XRender.

No.
Take a look at the link in message 1.

[Guest]

The problem came back after switching from OpenGL 3.1 to XRender but it only seems to affect the task bar for me (not sure if my environment being a VM is relevant). I rolled this back and tried changing the OpenGL interface to EGL instead, things are much better now!

[Gerii]

Even with XRender the screen sometimes goes completely black (usually a few minutes after logging in). Only killing my X Server helps in those cases.

[Gerii]

This is definitely related to sddm, now that I've switched to mdm this hasn't happened anymore.

[bdcomp]

This is definitely related to sddm, now that I've switched to mdm this hasn't happened anymore.

I opened a bug:
https://bugs.launchpad.net/ubuntu/+bug/1535763

I will appreciate if you comment at the bug report and mark it as affected by.

[sweasyf]

I have this same issue. I get the horizontal lines after a reboot. While the screen is crazy, I can still get a terminal with ALT-F2, then sudo enable sddm, let it do its thing. Then logout and it will drop back to the main sddm login screen and all is fine. Something is terribly wrong with the way sddm gets loaded now. I'm also getting a ton of errors from my usb soundcard, but I think I can solve that one. This one has me stumped. I can get to a working system, but if anyone else on the system powers down or reboots the system, it will be unusable until I can get in and force the sddm.service.

[bendy]

Not sure if it is related, but I get some mild flashing screen corruption when SDDM first loads, but this then settles down and doesn't stop me logging in. However, if I go to the Startup and Shutdown part of System Settings and click on Login Screen (SDDM) there are no settings or dialogs available.

So, I think somethings not quite right with SDDM on 5.5.3.

I'm using nvidia graphics with the binary driver.

[sweasyf]

My problems are only on the initial sddm load after a reboot. The screen is crazy then. After an ALT-F2, and blindly typing in the commands to force restart sddm, everything is OK. Somewhere between a good grub load and the initial sddm screen is the issue.

[sweasyf]

I'm going to try a few more things first, but I'm real close to doing a ppa-purge on the backports ppa. Apparently from the folks who have seen this issue before, that fixes it (at the expense of losing the newer plasma updates). That is not really a fix, that is Iron Maiden - Run to the Hills.