Bug 351390

Summary:	Corrupted kscreen config breaks KDE startup process
Product:	[Plasma] KScreen	Reporter:	Dik Takken <kde>
Component:	common	Assignee:	Daniel Vrátil <dvratil>
Status:	RESOLVED FIXED
Severity:	grave	CC:	kde, sebas
Priority:	NOR
Version:	5.3.2
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Content of .xsession-errors of a failing login session Output of kscreen-console bug kscreen profile 08d41bd4a94820782c6a9cee51a9df2d (working) kscreen profile 08d41bd4a94820782c6a9cee51a9df2d (corrupted) Output of kscreen-console bug, taken after step 7 in reproduction steps

Description Dik Takken 2015-08-17 08:49:10 UTC

Switching between various setups with external monitors sometimes results in a kscreen profile that appears to be corrupted: Any subsequent attempt to login on the system using that specific monitor setup will fail, throwing me back to the login screen as soon as kscreen is started.

Reproducible: Sometimes

Steps to Reproduce:
The kscreen config files appears to get corrupted when:

1. Laptop is suspended to RAM while disconnected from docking station
2. Laptop is docked
3. Laptop wakes up connected to the dock


Actual Results:  
The kscreen profile containing the docked configuration got corrupted. The next time I tried to login while docked failed and I got thrown back to the login screen. When I detached the laptop from the dock, or changed the external monitor setup, logging in worked just fine.

Deleting the corrupted kscreen profile fixed the problem.

Expected Results:  
Corrupted kscreen profiles should never cause KDE startup to fail. As a last resort, it should delete the corrupted profile and create a new one.

I marked this bug as 'grave', since it renders the system basically useless. If you do not have the technical knowledge to find the kscreen profile and delete it, you simply cannot login anymore.

Comment 1 Dik Takken 2015-08-17 08:52:55 UTC

Created attachment 94076 [details]
Content of .xsession-errors of a failing login session

Comment 2 Dik Takken 2015-08-17 08:54:19 UTC

Created attachment 94077 [details]
Output of kscreen-console bug

kscreen-console bug output run on the monitor configuration matching the attached kscreen profile 08d41bd4a94820782c6a9cee51a9df2d

Comment 3 Dik Takken 2015-08-17 08:55:08 UTC

Created attachment 94078 [details]
kscreen profile 08d41bd4a94820782c6a9cee51a9df2d (working)

Comment 4 Dik Takken 2015-08-17 08:55:38 UTC

Created attachment 94079 [details]
kscreen profile 08d41bd4a94820782c6a9cee51a9df2d (corrupted)

Comment 5 Dik Takken 2015-08-19 20:19:15 UTC

Ok, I experimented a bit more and the config corruption is 100% reproducible as follows:

1. Boot up laptop while connected to docking station with one external display attached
2. Configure the display setup to have the external monitor enabled, as primary display
3. Shut down the laptop
4. Disconnect the laptop from the dock, boot it up again, log in.
5. Suspend to RAM
6. Connect laptop to the dock, with one same external monitor attached.
7. Wake up the laptop.

At this point, the external monitor remains in stand by and the image on the laptop is a mashup of content from both screens. The mouse pointer cannot reach some parts of the screen. I ran kscreen-console bug, see the attachment below. In the output, you can see that it switches the primary screen to the external monitor, as it was configured to. However, you can also see that the external monitor is disabled.

8. Reboot the laptop, log in.
9. Login process fails, returns to login screen. KScreen profile has been corrupted.

Comment 6 Dik Takken 2015-08-19 20:22:54 UTC

Created attachment 94122 [details]
Output of kscreen-console bug, taken after step 7 in reproduction steps

Comment 7 Simone Gaiarin 2016-10-27 20:40:10 UTC

In my case it's not happening anymore in Plasma 5.8.2.

Comment 8 Sebastian Kügler 2016-11-10 10:47:31 UTC

Thanks Simone, for confirming. I have indeed fixed it in 5.8, so closing this report now.