Bug#1039878: gnome-shell: Many zombie xprop processes

[Stéphane Glondu]

Control: reassign -1 gnome-shell-extension-pixelsaver
Control: tags -1 - moreinfo

Le 29/06/2023 à 11:25, Simon McVittie a écrit :
>> I noticed there are many zombie "xprop" processes on my system, whose
>> parent is gnome-shell. They disappear when I restart the session, but
>> then start reappearing progressively.
> 
> gnome-shell doesn't have any mentions of xprop in its source code,
> so this is probably a Shell extension (which run as part of the
> gnome-shell process and are just as powerful as Shell itself, but with
> less experienced upstream maintainers). Please disable all extensions
> and see whether the problem persists.
> 
> Based on codesearch.debian.net I'm going to guess that you probably
> use gnome-shell-extension-pixelsaver, which is documented as "depends
> on Xorg's `xprop` and `xwininfo` utilities", and contains at least one
> suspicious use of GLib.SpawnFlags.DO_NOT_REAP_CHILD which seems likely
> to cause zombie processes.

Indeed, you seem to be right: after disabling this extension, xprop 
zombies are gone.

> (I don't know why pixelsaver is using xprop to communicate "please don't
> draw a titlebar", rather than making use of its ability to execute
> arbitrary code in gnome-shell to not draw the titlebar even if the app
> asked for one.)

-- 
Stéphane