Bug#1000498: segfaults in libst-1.0.so with "vertical overview" plugin enabled

[Detlev Zundel]

Hi Simon,

thanks for the quick reply!

> On Wed, 24 Nov 2021 at 10:50:29 +0100, Detlev Zundel wrote:
>> Having installed the "vertical overview" package, I experience segfaults in
>> gnome-shell killing the whole session.  I do think the addon is related as log
>> messages precede the segfaults.
>
> Is this reproducible if you disable the extension?

The crashes are not that frequent - sometimes it takes multiple days
before another crash so I only started seeing this relation while
collecting the data for the bug report.  But now that I think of it, I
did not experience segfaults before enabling the addon.  So I am pretty
sure but not 100%...

> Did you get this extension from Debian or from extensions.gnome.org?

I installed it from extensions.gnome.org and just checked that I do not
see it packaged for Debian bookworm.

> If an extension is causing a crash, there is usually not much that
> gnome-shell can do about it. Extensions work by "monkey-patching"
> the gnome-shell code, and have just as much control over execution as
> gnome-shell does.
>
>> Nov 17 17:42:40 krikkit gnome-shell[2918]: ../../../gobject/gsignal.c:2732:
>> instance '0x55db198ddf00' has no handler with id '10990'
>
> This suggests that something (presumably the vertical overview extension)
> is not keeping track of its signal handler IDs correctly.
>
>> Nov 17 17:42:40 krikkit kernel: gnome-shell[2918]: segfault at 55de45d1f627 ip
>> 00007f39f4900b29 sp 00007ffd73fdd360 error 4 in
>> libst-1.0.so[7f39f48de000+4b000]
>
> Can you get a backtrace from this crash? systemd-coredump is usually the
> easiest way to achieve this. See: https://wiki.debian.org/HowToGetABacktrace

I installed systemd-coredump and will report after the next occurrence.

Thanks
  Detlev