When kwin_wayland crashes

[Aleix Pol]

Hey,
Here's an issue I've seen and I'm pretty sure you've seen too. For any
reason kwin crashes. SDDM kills the whole session and jumps back to
the login UI

Tue 2018-05-15 15:22:30 CEST    669  1000  1000  11 truncated
/home/apol/devel/kde5/bin/kwin_wayland
Tue 2018-05-15 15:22:32 CEST  11004  1000  1000   6 present
/home/apol/devel/kde5/lib64/libexec/drkonqi
Tue 2018-05-15 15:22:32 CEST  11003  1000  1000   6 present
/home/apol/devel/kde5/lib64/libexec/org_kde_powerdevil
Tue 2018-05-15 15:22:32 CEST   1139  1000  1000   6 present
/usr/lib/chromium/chromium
Tue 2018-05-15 15:22:32 CEST    811  1000  1000   6 present
/home/apol/devel/kde5/lib64/libexec/org_kde_powerdevil


As you can see here, kwin crashes into a "truncated" state that
doesn't allow us to get a backtrace. My guess there is that it's SDDM
rushing to have it killed but I'm not sure that's actually the case.

Can anyone point me at what is actually happening on the SDDM side? I
was thinking that ideally when the session is open again we'd see a
kcrash dialog with the backtrace and the opportunity to report. Or at
the very least, we need to be able to successfully query coredumpd.

Aleix