alnikiforov added a comment.
I've managed to reproduce it and take a backtrace. It's an infinite recursion. Eventually stack's end is reached, although it takes some time to do it. Here's a piece of backtrace I got: #460 0x00007ffff64dcbec in KIdleTimePrivate::_k_resumingFromIdle (this=<optimized out>) at /usr/src/debug/kidletime-5.66.0/src/kidletime.cpp:244 #461 0x00007ffff6e14143 in QMetaObject::activate (sender=0x50aa40, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3803 #462 0x00007ffff7f4e9c4 in PowerDevil::Core::onResumingFromIdle (this=0x7fffe400cd30) at /usr/src/debug/powerdevil-5.17.5/daemon/powerdevilcore.cpp:820 #463 0x00007ffff7f89055 in PowerDevil::Core::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at /usr/src/debug/powerdevil-5.17.5/BUILD/daemon/powerdevilcore_autogen/EWIEGA46WW/moc_powerdevilcore.cpp:229 #464 0x00007ffff6e14143 in QMetaObject::activate (sender=0x50cac0, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3803 #465 0x00007ffff64dcbec in KIdleTimePrivate::_k_resumingFromIdle (this=<optimized out>) at /usr/src/debug/kidletime-5.66.0/src/kidletime.cpp:244 #466 0x00007ffff6e14143 in QMetaObject::activate (sender=0x50aa40, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3803 #467 0x00007ffff7f4e9c4 in PowerDevil::Core::onResumingFromIdle (this=0x7fffe400cd30) at /usr/src/debug/powerdevil-5.17.5/daemon/powerdevilcore.cpp:820 #468 0x00007ffff7f89055 in PowerDevil::Core::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at /usr/src/debug/powerdevil-5.17.5/BUILD/daemon/powerdevilcore_autogen/EWIEGA46WW/moc_powerdevilcore.cpp:229 #469 0x00007ffff6e14143 in QMetaObject::activate (sender=0x50cac0, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3803 #470 0x00007ffff64dcbec in KIdleTimePrivate::_k_resumingFromIdle (this=<optimized out>) at /usr/src/debug/kidletime-5.66.0/src/kidletime.cpp:244 #471 0x00007ffff6e14143 in QMetaObject::activate (sender=0x50aa40, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3803 #472 0x00007ffff7f4e9c4 in PowerDevil::Core::onResumingFromIdle (this=0x7fffe400cd30) at /usr/src/debug/powerdevil-5.17.5/daemon/powerdevilcore.cpp:820 #473 0x00007ffff7f89055 in PowerDevil::Core::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at /usr/src/debug/powerdevil-5.17.5/BUILD/daemon/powerdevilcore_autogen/EWIEGA46WW/moc_powerdevilcore.cpp:229 #474 0x00007ffff6e14143 in QMetaObject::activate (sender=0x50cac0, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3803 REPOSITORY R274 KIdleTime REVISION DETAIL https://phabricator.kde.org/D27279 To: broulik, #frameworks, davidedmundson Cc: alnikiforov, davidedmundson, kde-frameworks-devel, LeGast00n, cblack, GB_2, michaelh, ngraham, bruns