Bug 362005

Summary:	Hidden windows namebar, panel's taskbar entries and whole Plasma unusable
Product:	[Plasma] kscreenlocker	Reporter:	Germano Massullo <germano.massullo>
Component:	library	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED DOWNSTREAM
Severity:	grave	CC:	bhush94, mgraesslin, plasma-bugs, rdieter
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	screenshot xsession-errors

Description Germano Massullo 2016-04-20 16:22:49 UTC

Note: this bug has been successfully reproduced on 5 different machines, 
Fedora 23: I updated from Plasma 5.5.5 to 5.6.2 and now after the login:
- every single window's namebar is not shown, you cannot resize, minimize, maximize it;
- panel's taskbar entries are missing
- the panel size is wrong (see screenshot) and you cannot extend it back again
- the whole Plasma is unusable

I also need help in starting GDB and Valgrind from TTY since I cannot use "kquitapp5 plasmashell" and again "gdb plasmashell", because Konsole will disappear as soon Plasma restarts.
Guide https://techbase.kde.org/Development/Tutorials/Debugging/Debugging_with_GDB  does not help.

I have been able to reproduce this bug on 2 real machines and 3 virtual machines

Reproducible: Always

Comment 1 Germano Massullo 2016-04-20 16:23:14 UTC

Created attachment 98477 [details]
screenshot

Comment 2 Germano Massullo 2016-04-20 16:24:57 UTC

Created attachment 98478 [details]
xsession-errors

Comment 3 Germano Massullo 2016-04-20 16:26:27 UTC

Ops I forgot to delete the first line of message

Comment 4 Germano Massullo 2016-04-20 16:28:26 UTC

Fedora bugreport https://bugzilla.redhat.com/show_bug.cgi?id=1328942

Comment 5 Rex Dieter 2016-04-20 16:44:17 UTC

Appears user updated to kwin-5.6.x , but (probably) missed upgrading kscreenlocker-5.6.x along with it (and tried using kscreenlocker-5.5.x), resulting in missing symbols:

kwin_x11: symbol lookup error: /lib64/libkwin.so.5: undefined symbol: _ZN12ScreenLocker7KSldApp16lockStateChangedEv

Shouldn't libKScreenLocker soname get bumped for the new symbol?

Comment 6 Germano Massullo 2016-04-20 16:45:56 UTC

The problem was that entering
# dnf update kf* plasm* --enablerepo=updates-testing
the system did not update kscreenlocker package

Comment 7 Rex Dieter 2016-04-20 16:49:39 UTC

It's not resolved (re-opening), I'd still argue upstream should consider bumping  libKScreenLocker soname

Comment 8 Rex Dieter 2016-04-20 16:50:17 UTC

triaging to kscreenlocker component

Comment 9 Germano Massullo 2016-04-20 16:51:57 UTC

Ok

Comment 10 Martin Flöser 2016-04-21 05:42:16 UTC

sorry kscreenlocker is not yet in a quality from library point of view that we can ensure it's properly so-bumped. It doesn't follow any library guidelines, no d-ptr, etc. etc.

kscreenlocker is part of Plasma and used in plasma-workspace and KWin. Those products release together and need to be updated in lock-step anyway.

If distributions cannot ensure that those get updated together, please so-bump kscreenlocker manually.

Comment 11 Rex Dieter 2016-04-21 12:12:11 UTC

Fair enough, but I'm curious how distributors (or users even) are expected to know that which libraries can be trusted to be "properly so-bumped", "follow any library guidelines", etc...

I'd go so far as say if you cannot guarantee soname compatibility, then some suggestions to help make that clearer to everyone:
* clearly advertise/document it
* bump soname for *every* release, or even don't use a soname at all
* name the library to make it painfully obvious, ie, use "private" or "experimental" in the library name

Comment 12 Martin Flöser 2016-04-21 14:10:22 UTC

If I had enough time for this I would have made it a proper library. Alas I didn't have the time. This included that I didn't have the time to so-bump it. And it also didn't occur to me as the products are released together. Sorry about that.