[Wayland] plasma crashes and cannot attach gdb to kwin_wayland

[Martin Gräßlin]

Am 2017-04-13 17:19, schrieb Germano Massullo:
> Il 13/04/2017 16:49, Martin Gräßlin ha scritto:
>> Am 2017-04-13 16:08, schrieb Germano Massullo:
>>> Il 13/04/2017 13:12, David Edmundson ha scritto:
>>>> ​"echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope"  (or run GDB
>>>> as root)
>>>> 
>>>> David
>>> As root in tty3 I attached GDB to kwin_wayland and as soon I got back 
>>> to
>>> the graphical session, the system got stuck and I could not neither
>>> return back to tty3, so I had to use Magic SysRq key to restart the
>>> system.
>>> The wiki says to try to use SSH, but it would be useless too since I 
>>> am
>>> not able to use the graphical session if kwin_wayland is attached to 
>>> GDB
>> 
>> Of course you need to continue once you attached gdb. I'm not sure
>> what you want to achieve but debugging the running display manager on
>> the same system - well it's even more impossible than debugging the
>> running window manager on X11. I'm working with nested kwin_wayland
>> running in gdb to do debugging.
>> 
>> Cheers
>> Martin
>> 
> 
> A running from bash Plasma, when it crashes[1], sends a message like
>> The Wayland connection broke. Did the Wayland compositor die?
> so I was trying to figure out if kwin_wayland crashes too
> [1]: https://bugs.kde.org/show_bug.cgi?id=378707

I think you are looking at a false positive here. Given the backtrace I 
think the message is a side effect not the cause. If the Wayland server 
had problems everything would die not just Plasma. And it would not 
crash - at least not directly. It could only crash in the cleanup 
handler and that's not the case here.

Cheers
Martin