kwin (kwin_x11) git 9b7ab4d16 builds but segfault-loops, while the previous commit 80d3f148e builds and runs fine. Distro/arch-level: Gentoo/~amd64 Frameworks/plasma version: git master using the gentoo/kde overlay ebuilds Qt version: 5.14.1 Kernel: Linux 5.6-git (currently rc7+2, commit 979e52ca0) Graphics environment: xorg-server 1.20.7, mesa 20.0.2 Graphics hardware: AMD Radeon RX 460 (Polaris 11), freedomware drivers Screen layout: 2 4K TVs as monitors, side-by-side layout for a total 7680x2160 resolution. Upon reboot and restarting X/plasma (startx with plasma as the session) after an update, I got the kwin crashed too many times dialog. I don't have any other window managers installed so there wasn't much to do but rebuild it from an earlier commit. Fortunately I have ccache setup so the rebuild doesn't take long. I had updated only a few days previously so there weren't many commits to bisect and it turned out head (9b7ab4d16) was the culprit. I normally run an aurora windeco and multi-monitor but tried breeze and single monitor, but that didn't help. Additionally, I tried suspending compositing, to no avail. That commit simply won't run.
Do you have a backtrace?
Commit is: Author: Aleix Pol <aleixpol@kde.org> Date: Mon Mar 23 20:26:21 2020 +0100 Improve tests behaviour on set ups with high dpi
I assume Screens::self()->size(0) seg faults if out of range.
Can reproduce
Thread 1 "kwin_x11" received signal SIGSEGV, Segmentation fault. 0x00007ffff7cfe393 in KWin::Screens::physicalDpiX (this=0x0, screen=0) at /home/david/projects/kde5/src/kde/workspace/kwin/screens.cpp:234 234 return size(screen).width() / physicalSize(screen).width() * qreal(25.4); (gdb) bt #0 0x00007ffff7cfe393 in KWin::Screens::physicalDpiX(int) const (this=0x0, screen=0) at /home/david/projects/kde5/src/kde/workspace/kwin/screens.cpp:234 #1 0x00007ffff7cef583 in KWin::ScreenEdges::ScreenEdges(QObject*) (this=0x555555634c00, parent=0x5555556c35f0) at /home/david/projects/kde5/src/kde/workspace/kwin/screenedge.cpp:730 #2 0x00007ffff7cef434 in KWin::ScreenEdges::create(QObject*) (parent=0x5555556c35f0) at /home/david/projects/kde5/src/kde/workspace/kwin/screenedge.cpp:711 #3 0x00007ffff7da52a6 in KWin::Workspace::Workspace(QString const&) (this=0x5555556c35f0, sessionKey="") at /home/david/projects/kde5/src/kde/workspace/kwin/workspace.cpp:162 #4 0x00007ffff7c8ae3e in KWin::Application::createWorkspace() (this=0x7fffffffde68) at /home/david/projects/kde5/src/kde/workspace/kwin/main.cpp:279 #5 0x0000555555560152 in KWin::ApplicationX11::performStartup()::$_1::operator()() const::{lambda()#1}::operator()() const (this=0x5555556c7430) at /home/david/projects/kde5/src/kde/workspace/kwin/main_x11.cpp:252 #6 0x00005555555600f6 in QtPrivate::FunctorCall<QtPrivate::IndexesList<>, QtPrivate::List<>, void, KWin::ApplicationX11::performStartup()::$_1::operator()() const::{lambda()#1}>::call({lambda()#1}&, void**) (f=..., arg=0x7fffffffd360) at /opt/qt5/include/QtCore/qobjectdefs_impl.h:146 #7 0x00005555555600c1 in QtPrivate::Functor<KWin::ApplicationX11::performStartup()::$_1::operator()() const::{lambda()#1}, 0>::call<QtPrivate::List<>, void>({lambda()#1}&, void*, {lambda()#1}&*) (f=..., arg=0x7fffffffd360) at /opt/qt5/include/QtCore/qobjectdefs_impl.h:256 #8 0x000055555556006c in QtPrivate::QFunctorSlotObject<KWin::ApplicationX11::performStartup()::$_1::operator()() const::{lambda()#1}, 0, QtPrivate::List<>, void>::impl(int, QtPrivate::QSlotObjectBase*, QObject*, void**, bool*) (which=1, this_=0x5555556c7420, r=0x7fffffffde68, a=0x7fffffffd360, ret=0x0) at /opt/qt5/include/QtCore/qobjectdefs_impl.h:439 #9 0x00007ffff34c37df in QtPrivate::QSlotObjectBase::call(QObject*, void**) (this=0x5555556c7420, r=0x7fffffffde68, a=0x7fffffffd360) at ../../include/QtCore/../../../../qt5/qtbase/src/corelib/kernel/qobjectdefs_impl.h:394 #10 0x00007ffff350506e in doActivate<false>(QObject*, int, void**) (sender=0x55555562d810, signal_index=3, argv=0x7fffffffd360) at /home/david/projects/qt5/qtbase/src/corelib/kernel/qobject.cpp:3870 #11 0x00007ffff34fea4b in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) (sender=0x55555562d810, m=0x7ffff7fb01e0 <KWin::Platform::staticMetaObject>, local_signal_index=0, argv=0x0) at /home/david/projects/qt5/qtbase/src/corelib/kernel/qobject.cpp:3930 #12 0x00007ffff7b051d2 in KWin::Platform::screensQueried() (this=0x55555562d810) at kwin_autogen/EWIEGA46WW/moc_platform.cpp:318 #13 0x00007fffecd0df78 in KWin::X11StandalonePlatform::init() (this=0x55555562d810) at /home/david/projects/kde5/src/kde/workspace/kwin/plugins/platforms/x11/standalone/x11_platform.cpp:108 #14 0x000055555555fcc0 in KWin::ApplicationX11::performStartup()::$_1::operator()() const (this=0x5555556341b0)
Git commit 754b90c72f8c73d8dcf7091fba82309d21aebbb5 by David Edmundson. Committed on 24/03/2020 at 12:40. Pushed by davidedmundson into branch 'master'. Create screens before screen edges Summary: Screens is used in screenEdges in a recent refactor This didn't affect wayland as main_wayland creates screens earlier itself. We can't move creation into main_x11 as X11's screens uses an event filter which relies on workspace existing. Test Plan: Restarted on X11 Reviewers: #kwin Subscribers: kwin Tags: #kwin Differential Revision: https://phabricator.kde.org/D28233 M +1 -1 workspace.cpp https://commits.kde.org/kwin/754b90c72f8c73d8dcf7091fba82309d21aebbb5
Fix verified. Thanks. =:^)