Bug 502213

Summary: The screen locked and wouldn't unlock
Product: [Plasma] plasmashell Reporter: php4fan
Component: generalAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: grave CC: kde, nate, nicolas.fella
Priority: NOR    
Version First Reported In: 6.3.3   
Target Milestone: 1.0   
Platform: Manjaro   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description php4fan 2025-03-30 19:33:13 UTC
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SUMMARY

This has just happened to me randomly, I have no idea how to reproduce at will. Regardless, this is a hugely critical bug that should have the topmost priority.

STEPS TO REPRODUCE

This WILL NOT reproduce systematically, but this is what I did and what happened

1. I didn't touch the keyboard or mouse for a few minutes, so the screen locked automatically as it usually does
2. I shaked the mouse to bring up the password prompt
3. I entered the password and hit Enter. 

OBSERVED RESULT

Nothing f*****g happened. It didn't show any error message. It was just as if I wasn't hitting Enter. I also tried the "->" button  next to the password input, but it did nothing either. The password I entered was obviously correct. I deleted it and retyped a few times.

 I could not regain control of my own f*****g session. I had to do Ctrl+Alt+F3 and reboot from there to be able to access my computer again. Whatever I had open and unsaved in any running application was lost.

This is absolutely outrageous.

I'm probably not reporting this against the correct component, but I have no idea what it is. Please move where appropriate.


EXPECTED RESULT
Obviously should unlock screen when entering the password


SOFTWARE/OS VERSIONS
Operating System: Manjaro Linux 
KDE Plasma Version: 6.3.3
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2
Kernel Version: 6.6.83-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 12 × 12th Gen Intel® Core™ i7-1255U
Memory: 15.3 GiB of RAM
Graphics Processor: Intel® Iris® Xe Graphics
Manufacturer: ASUSTeK COMPUTER INC.
Product Name: Vivobook_ASUSLaptop X1502ZA_F1502ZA
System Version: 1.0
Qt Version: 

ADDITIONAL INFORMATION
Comment 1 php4fan 2025-03-30 19:41:25 UTC
I now see that next time this happens I can do "loginctl unlock-session 1" instead of rebooting.
Still, most users won't know this and will be forced to reboot, so the issue is critical.
Comment 2 php4fan 2025-03-30 23:14:40 UTC
Just realized something.

Normally, when the screen goes to lock, if I am quick enough to shake the mouse, it will unlock immediately without having to insert the password. I assume that's intended. I do that pretty often, when I'm thinking in front of the screen and not touching keyboard and mouse, and I notice that it's going to lock. 
I'm not sure if the password prompt is supposed to have the time to become visible in that case (or if it's only supposed to show an empty screen and then go back immediately to the desktop as you shake the mouse without ever transitioning to the password prompt screen) but it definitely often does show up for a brief moment, even though it then immediately goes away without having to actually insert the password.

When the issue happened, this was one of those cases.

So I'm thinking: MAYBE, just maybe, there's a race condition such that, if you shake the mouse exactly at the right (or rarther the wrong) time, just barely after the screen has gotten locked, the system "thinks" that you shook the mouse soon enough to prevent locking, but actually you didn't, so the password prompt is visible (and interactive), but the system "doesn't know" that it's required and therefore ignores it.

Maybe it's nothing like that, I don't know, it's just a hypothesis. I've seen bugs  this stupid, I wouldn't be surprised.
Comment 3 php4fan 2025-03-30 23:16:41 UTC
> When the issue happened, this was one of those cases.

I meant it was one of those cases where I shake the mouse immediately as I notice that the screen changes. Obviously in this case it wasn't fast enough to prevent locking - that's the whole point.
Comment 4 Nicolas Fella 2025-03-31 09:24:08 UTC
I understand you are frustrated, but this kind of language is not helping you in any way. Please keep this in mind for future reports
Comment 5 php4fan 2025-03-31 09:33:25 UTC
How is this importance "normal"???
Comment 6 Nate Graham 2025-03-31 20:30:00 UTC
It should be higher than "normal", but your poor behavior caused Nicolas to over-react in changing the severity. Please try to communicate in a more neutral way, even when the problem is very severe. This will help avoid pointless arguments and hurt feelings. Thanks.

Either way, duplicate of Bug 484363.

*** This bug has been marked as a duplicate of bug 484363 ***
Comment 7 Nate Graham 2025-05-15 13:59:28 UTC

*** This bug has been marked as a duplicate of bug 500339 ***