Bug 465469

Summary: konsole hangs after a program in one tab emitted many BEL characters
Product: [Applications] konsole Reporter: Bruno Haible <bruno>
Component: generalAssignee: Konsole Bugs <konsole-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: crash    
Priority: NOR    
Version First Reported In: 21.12.3   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: list of threads
stack trace of the main thread

Description Bruno Haible 2023-02-08 12:27:28 UTC
Created attachment 156070 [details]
list of threads

SUMMARY
After using a program in one tab (namely, GNU info), that spews many BEL characters in short time, and switching to a different tab, konsole become unresponsive, hanging on a lock.

STEPS TO REPRODUCE
1. I used konsole with many tabs for more than 2 months, without problems.
2. In one tab, I ran 'info m4', searched for m4_provide_if, then attempted to abort this search by pressing some of the characters ESC, Enter, Ctrl-Q, repeatedly.
3. I switched to a different tab.
4. At this point many notification popups appeared, each notifying me of a BEL being emitted to the tab where 'info m4' was running.
5. As 'top' showed me that konsole was eating 200% CPU time, I killed the 'info' program.
6. Now konsole was still eating 100% CPU time, and additionally was unresponsive (could not type into the current tab, could not switch to another tab, could not get a menu to open).
7. I got debugging infos from the konsole process ("sudo gdb /usr/bin/konsole 2669").
8. I killed the konsole, thereby losing the state of all tabs (equivalent to when konsole had crashed).

OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Ubuntu 22.04
KDE Plasma Version: 5.24.6
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3

ADDITIONAL INFORMATION
Comment 1 Bruno Haible 2023-02-08 12:28:23 UTC
Created attachment 156071 [details]
stack trace of the main thread
Comment 2 Kurt Hindenburg 2023-04-28 22:28:09 UTC
I assume you have the "Terminal Bell mode" to the default "System Notifications"?  

Konsole only sends a notification every 500ms even though I did manage to get high CPU.   I wonder if that should be increased.
Comment 3 Kurt Hindenburg 2023-04-28 22:46:42 UTC

*** This bug has been marked as a duplicate of bug 463126 ***