Systemsettings *always* crashes by segfault when I open "Display and Monitor" with multiple monitors (my laptop monitor and VGA monitor). My environments (on Arch Linux): - systemsettings 5.9.5-1 - kscreen 5.9.5-1 - libkscreen 5.9.5-1 - qt5-base 5.8.0-10 - freetype2 2.7.1-1 Way to reproduce: 1. boot machine with VGA monitor 2. login with sddm 3. launch systemsettings 4. go to "Display and Monitor" 5. systemsettings crashed Expected results: Open display configuration window. Logs: (belows are the result of 'journalctl -ef' when doing "way to reproduce") Apr 29 20:21:59 Erika systemsettings5[3222]: kscreen.kcm: LOAD Apr 29 20:21:59 Erika systemsettings5[3222]: kscreen.kcm: Activate output 66 Apr 29 20:21:59 Erika kernel: systemsettings5[3222]: segfault at 7ffd1166dfd0 ip 00007fca815625e0 sp 00007ffd1166dfd0 error 6 in libfreetype.so.6.13.0[7fca81534000+ba000] Apr 29 20:21:59 Erika kwin_x11[759]: QXcbConnection: XCB error: 3 (BadWindow), sequence: 31470, resource id: 104857605, major code: 15 (QueryTree), minor code: 0 $ xrandr Screen 0: minimum 8 x 8, current 1440 x 1024, maximum 32767 x 32767 LVDS1 connected primary 1440x900+0+0 (normal left inverted right x axis y axis) 260mm x 160mm 1440x900 50.00*+ 1280x800 50.00 720x450 50.00 DP1 disconnected (normal left inverted right x axis y axis) HDMI1 disconnected (normal left inverted right x axis y axis) VGA1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 360mm x 290mm 1280x1024 60.02 + 75.02* 1152x864 75.00 1024x768 75.03 60.00 832x624 74.55 800x600 75.00 60.32 640x480 75.00 59.94 720x400 70.08 VIRTUAL1 disconnected (normal left inverted right x axis y axis $ dmesg | grep -i error [ 4.823428] tpm tpm0: A TPM error (6) occurred attempting to read a pcr value [ 1041.929787] systemsettings5[3132]: segfault at 7ffd93034f90 ip 00007fed9bffc5e0 sp 00007ffd93034f90 error 6 in libfreetype.so.6.13.0[7fed9bfce000+ba000] [ 1083.512945] systemsettings5[3222]: segfault at 7ffd1166dfd0 ip 00007fca815625e0 sp 00007ffd1166dfd0 error 6 in libfreetype.so.6.13.0[7fca81534000+ba000] $ lspci 00:00.0 Host bridge: Intel Corporation Core Processor DRAM Controller (rev 02) 00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02) 00:16.0 Communication controller: Intel Corporation 5 Series/3400 Series Chipset HECI Controller (rev 06) 00:19.0 Ethernet controller: Intel Corporation 82577LM Gigabit Network Connection (rev 06) 00:1a.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06) 00:1b.0 Audio device: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio (rev 06) 00:1c.0 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 1 (rev 06) 00:1c.3 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 4 (rev 06) 00:1c.4 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 5 (rev 06) 00:1d.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06) 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev a6) 00:1f.0 ISA bridge: Intel Corporation QM57 Chipset LPC Interface Controller (rev 06) 00:1f.2 SATA controller: Intel Corporation 5 Series/3400 Series Chipset 6 port SATA AHCI Controller (rev 06) 00:1f.3 SMBus: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller (rev 06) 00:1f.6 Signal processing controller: Intel Corporation 5 Series/3400 Series Chipset Thermal Subsystem (rev 06) 02:00.0 Network controller: Intel Corporation Wireless 7260 (rev bb) 05:00.0 USB controller: Renesas Technology Corp. uPD720202 USB 3.0 Host Controller (rev 02) ff:00.0 Host bridge: Intel Corporation Core Processor QuickPath Architecture Generic Non-core Registers (rev 02) ff:00.1 Host bridge: Intel Corporation Core Processor QuickPath Architecture System Address Decoder (rev 02) ff:02.0 Host bridge: Intel Corporation Core Processor QPI Link 0 (rev 02) ff:02.1 Host bridge: Intel Corporation 1st Generation Core i3/5/7 Processor QPI Physical 0 (rev 02) ff:02.2 Host bridge: Intel Corporation 1st Generation Core i3/5/7 Processor Reserved (rev 02) ff:02.3 Host bridge: Intel Corporation 1st Generation Core i3/5/7 Processor Reserved (rev 02)
If this is reproducible, please add the backtrace for the crash. For more information, please see https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
Created attachment 105391 [details] backtrace of systemsettings5 using gdb Here is backtrace for systemsetting5 using gdb. It seems that below would be infinite loop: 0x00007ffff5999f5f in QFontEngine::alphaMapForGlyph(unsigned int, QFixed, QTransform c 0x00007fffe7861b1d in QFontEngineFT::alphaMapForGlyph(unsigned int, QFixed, QTransform 0x00007fffe7859e4e in QFontEngineFT::alphaMapForGlyph(unsigned int, QFixed) () from /usr/lib/libQt5XcbQpa.so.5
Yes, there is a recursion in QFontEngine. Please report this issue directly to Qt developers via https://bugreports.qt.io/
Thank you. I reported this issue by https://bugreports.qt.io/browse/QTBUG-60697.