https://bugs.kde.org/show_bug.cgi?id=423131
Bug ID: 423131
Summary: powerdevil does not release pending Inhibit cookie if
source application exits too quickly
Product: Powerdevil
Version: 5.19.1
Platform: Gentoo Packages
OS: Linux
Status: REPORTED
Severity: normal
Priority: NOR
Component: general
Assignee: plasma-b...@kde.org
Reporter: gabemarc...@yahoo.com
Target Milestone: ---
SUMMARY
Powerdevil delays registering an Inhibit request from dbus for 5 seconds
(commit eca79138c). If the requesting application/service dies during those 5
seconds, the Inhibit is still registered.
STEPS TO REPRODUCE
1. Launch an application that sends a request to Inhibit via
org.freedesktop.PowerManagement.Inhibit.Inhibit or directly to Powerdevil via
its dbus interface. I used the elisa music player.
2. Have said application send an Inhibit. With elisa, just play some music.
3. Exit the application before 5 seconds after sending an Inhibit. With elisa,
that's just exiting the application quickly after pressing play.
OBSERVED RESULT
Using:
watch -n1 dbus-send --session --dest=org.kde.Solid.PowerManagement.PolicyAgent
--type=method_call --print-reply /org/kde/Solid/PowerManagement/PolicyAgent
org.kde.Solid.PowerManagement.PolicyAgent.ListInhibitions
A new inhibition is listed after the application has exited, 5 seconds after
the inhibit was sent.
EXPECTED RESULT
No new inhibition is listed by the application that just exited.
SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Gentoo Linux (unstable)
(available in About System)
KDE Plasma Version: 5.19.1
KDE Frameworks Version: 5.71.0
Qt Version: 5.15.0
ADDITIONAL INFORMATION
I found this while debugging bug #421662 . While arguably elisa should be
sending an inhibit on a controlled exit (it can't reasonably do this if it gets
a SIGTERM or SIGKILL, or triggers a SIGSEGV, though), there is code in
Powerdevil to handle cases where the external service exits without getting rid
of the inhibitor. In fact, if I exit elisa after the Inhibit has posted
successfully, I do see the Inhibit being removed by Powerdevil.
The root of the problem is that currently, due to commit eca79138c, Powerdevil
quasi-registers the pending request, but it doesn't actually fully register it
so that the service is being listened to in case it dies. Specifically, in
daemon/powerdevilpolicyagent.cpp:
m_busWatcher.data()->addWatchedService(service);
isn't called until after the 5 second timer goes off.
>From what I can tell, this file hasn't changed since 5.19.1 and the current
master commit b009a7d856220b9ca64e34cc887069798c801fe9.
I'm experimenting to see what could be a possible solution, but I'm not
familiar with the codebase. In addition, due to contract clauses with my
employer, I can't provide patches without their permission, at least until I am
no longer employed by them. I may be able to provide ideas, though, once I come
up with something that works.
--
You are receiving this mail because:
You are watching all bug changes.
