Cannot get past sddm login screen in Kubuntu Vivid

Bug #1440151 reported by Donatas Glodenis
This bug affects 5 people
Affects Status Importance Assigned to Milestone
sddm (Ubuntu)
Nominated for Vivid by Alberto Salvia Novella

Bug Description

Couple days ago I installed Kubuntu Vivid on Lenovo Thinkpad x220 tablet (amd64 version from daily iso). Encrypted home directory, SSD type drive.

Today I could not enter my Plasma desktop. The sddm display manager gets stuck after I fill in the password and press Enter. Sometimes the mouse pointer disappears, and sometimes it turns into a black X symbol. It hangs like this till I kill it (sudo service sddm restart)

I can login to tt1-6 allright.

I tried installing slim and lxdm managers, but they do the same - get stuck after filling the password (mouse pointer disappears). I also tried reinstalling sddm (it updated two times in the repositories even today, so I updated to the new verisons, to no avail).

I have no clue how to troubleshoot this problem. Please tell me. If it is done sooner than sunday, I will try to gather whatever information I can from the system. Otherwise I will have to reinstall Kubuntu (perhaps 14.10 version) as I do need that machine to function.

There are other reports of this happening: - forum user molecule-eye comments. - comment on 21/3/2015 by Mike.

Revision history for this message
Ubuntu Foundations Team Bug Bot (crichton) wrote :

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tags: added: bot-comment
affects: ubuntu → sddm (Ubuntu)
Revision history for this message
Donatas Glodenis (dgvirtual) wrote :

since there is a possibility, that it is sddm bug, I am attaching related output.

Revision history for this message
Donatas Glodenis (dgvirtual) wrote :
Revision history for this message
Launchpad Janitor (janitor) wrote :

Status changed to 'Confirmed' because the bug affects multiple users.

Changed in sddm (Ubuntu):
status: New → Confirmed
Revision history for this message
Sergio Callegari (callegar) wrote :

I think that the issue is not the login manager. Problem happens also if I switch to lightdm. See kwin going to 100% CPU. Moving to xubuntu desktop fixes the problem. Once more KDE new version has been made the default too early I suppose.

Changed in sddm (Ubuntu):
importance: Undecided → Critical
Revision history for this message
Sergio Callegari (callegar) wrote :

In my case, the issue was the following:

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Alberto Salvia Novella (es20490446e) wrote :

  1. Report to <>.
  2. Paste the new report URL here.
  3. Set this bug status back to "confirmed".

Thank you.

Changed in sddm (Ubuntu):
status: Confirmed → Incomplete
tags: added: asked-to-upstream
Revision history for this message
hegemon8 (pantokrata2) wrote :

For me all was good on Kubuntu 20.04 until today when i've updated. Mind fact i have changed global theme, and other colorful stuff, icons cursors prior update, so i'm guessing it didn't cause it.
But i see black screen (not even backlight) but i can still log in typing password blindly. After that system acts normally.

Revision history for this message
hegemon8 (pantokrata2) wrote :

After 5 reboots it was the same, but i left it off few hours and when i'm back now on it, it seems to be working for me. But if any of output of command needed, i can help with that.

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