Bug 508917

SUMMARY
When I plug and unplug a monitor into a computer quickly, the kernel fails to load DPCD, kwin_wayland fails to load EDID, and Wayland client apps crash with "not a valid new object id (4278190410), message data_offer(n)".

STEPS TO REPRODUCE
1. Quickly plug and unplug a display cable before the kernel can finish reading its EDID information.

I have two monitors, a HDMI cable to a BenQ GL2760H, and a Benfei USBC-to-VGA adapter (from Amazon, dp/B076X2XS9R, IDK the chipset) to a VX720 CRT with overridden EDID.
The CRT feeds through a VGA 4-port switch that only allows me to cycle inputs sequentially, hence when I switch inputs sometimes I connect the CRT to my computer for a split-second. I noticed this would trigger plasmashell crashes.

OBSERVED RESULT
Background: I found that Linux labels the HDMI port as DP-1, and USB-C alt mode (to VGA) as DP-2.

If I briefly plug the CRT (which is not enabled) into the DAC and unplug the VGA side (the DAC remains in the computer), the kernel and kwin can't read the EDID, plasmashell and/or powerdevil crash.

Aug 29 20:46:35 ivy-fedora kernel: i915 0000:00:02.0: [drm] *ERROR* Failed to read DPCD register 0x92
Aug 29 20:46:36 ivy-fedora kwin_wayland[1953]: kwin_wayland_drm: Could not find edid for connector DrmConnector(id=112, gpu="/dev/dri/card1", name="DP-2", connection="Connected", countMode=5)
Aug 29 20:46:38 ivy-fedora plasmashell[78388]: not a valid new object id (4278190122), message data_offer(n)
Aug 29 20:46:38 ivy-fedora plasmashell[78388]: The Wayland connection experienced a fatal error: Invalid argument
Aug 29 20:46:38 ivy-fedora systemd[1639]: plasma-plasmashell.service: Main process exited, code=exited, status=255/EXCEPTION

(I tried attaching gdb to plasmashell, but it did not break on the Wayland error site leading to program termination.)

----

If I plug and unplug the LCD's HDMI cable (I think the kernel reads the EDID, and KDE tries switching from the CRT to LCD), kwin itself crashes.

(filtered journal:)
Aug 29 20:57:40 ivy-fedora kwin_wayland[1953]: kwin_wayland_drm: Atomic modeset test failed! Invalid argument
Aug 29 20:57:40 ivy-fedora kwin_wayland[1953]: kwin_wayland_drm: Atomic modeset test failed! Invalid argument
Aug 29 20:57:40 ivy-fedora kwin_wayland[1953]: kwin_xwl: Could not find a matching X RandR CRTC/output to set as primary for KWin::DrmOutput(0x555cc48d8950, name="DP-1", geometry=QRect(0,0 1920x1080), scale=1)
Aug 29 20:57:41 ivy-fedora audit[1953]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=3 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=1953 comm="kwin_wayland" exe="/usr/bin/kwin_wayland" sig=11 res=1
Aug 29 20:57:41 ivy-fedora kwin_wayland[1953]: kwin_xwl: Could not find a matching X RandR CRTC/output to set as primary for KWin::DrmOutput(0x555cc2b5e8d0, name="DP-2", geometry=QRect(0,0 1152x864), scale=1)
Aug 29 20:57:41 ivy-fedora kwin_wayland_wrapper[1953]: KCrash: Application 'kwin_wayland' crashing... crashRecursionCounter = 2
Aug 29 20:57:41 ivy-fedora kwin_wayland[1953]: kwin_xwl: Could not find a matching X RandR CRTC/output to set as primary for KWin::DrmOutput(0x555cc2b5e8d0, name="DP-2", geometry=QRect(0,0 1152x864), scale=1)
Aug 29 20:57:41 ivy-fedora kwin_wayland[1953]: kwin_xwl: Could not find a matching X RandR CRTC/output to set as primary for KWin::DrmOutput(0x555cc2b5e8d0, name="DP-2", geometry=QRect(0,0 1152x864), scale=1)
Aug 29 20:57:41 ivy-fedora kwin_wayland[1953]: kwin_xwl: Could not find a matching X RandR CRTC/output to set as primary for KWin::DrmOutput(0x555cc2b5e8d0, name="DP-2", geometry=QRect(0,0 1152x864), scale=1)
Aug 29 20:57:41 ivy-fedora systemd-coredump[80628]: Process 1953 (kwin_wayland) of user 1000 terminated abnormally with signal 11/SEGV, processing...

backtrace:
Thread 1 (Thread 0x7f9cbfb17300 (LWP 1953)):
[KCrash Handler]
#4  0x00007f9cc8fd6f89 in KWin::ColorManagementOutputV1::ColorManagementOutputV1 (this=0x7f9c91709c70, client=<optimized out>, id=<optimized out>, version=<optimized out>, output=0x0) at /usr/src/debug/kwin-6.4.4-2.fc42.x86_64/src/wayland/colormanagement_v1.cpp:580
#5  KWin::ColorManagerV1::wp_color_manager_v1_get_output (this=<optimized out>, resource=<optimized out>, id=<optimized out>, output=<optimized out>) at /usr/src/debug/kwin-6.4.4-2.fc42.x86_64/src/wayland/colormanagement_v1.cpp:63
#6  0x00007f9cc42cd056 in ffi_call_unix64 () at ../src/x86/unix64.S:104
#7  0x00007f9cc42c8d08 in ffi_call_int (cif=cif@entry=0x7ffdd4978d40, fn=fn@entry=0x7f9cc90ee510 <QtWaylandServer::wp_color_manager_v1::handle_get_output(wl_client*, wl_resource*, unsigned int, wl_resource*)>, rvalue=<optimized out>, rvalue@entry=0x0, avalue=avalue@entry=0x7ffdd4978e10, closure=closure@entry=0x0) at ../src/x86/ffi64.c:673
#8  0x00007f9cc42cb70e in ffi_call (cif=cif@entry=0x7ffdd4978d40, fn=0x7f9cc90ee510 <QtWaylandServer::wp_color_manager_v1::handle_get_output(wl_client*, wl_resource*, unsigned int, wl_resource*)>, rvalue=rvalue@entry=0x0, avalue=avalue@entry=0x7ffdd4978e10) at ../src/x86/ffi64.c:710
#9  0x00007f9cc7012440 in wl_closure_invoke (closure=closure@entry=0x555cc39033f0, target=<optimized out>, target@entry=0x555cc2ecf610, opcode=opcode@entry=1, data=<optimized out>, data@entry=0x555cc30a7180, flags=2) at ../src/connection.c:1241
#10 0x00007f9cc7017aa0 in wl_client_connection_data (fd=<optimized out>, mask=<optimized out>, data=<optimized out>) at ../src/wayland-server.c:483
#11 0x00007f9cc7015f42 in wl_event_loop_dispatch (loop=0x555cc17cbeb0, timeout=<optimized out>) at ../src/event-loop.c:1059
#12 0x00007f9cc8fe3669 in KWin::Display::dispatchEvents (this=<optimized out>) at /usr/src/debug/kwin-6.4.4-2.fc42.x86_64/src/wayland/display.cpp:138
#13 0x00007f9cc5f657ba in QtPrivate::QSlotObjectBase::call (this=0x555cc28ee4c0, r=0x555cc17e7430, a=0x7ffdd4979420) at /usr/src/debug/qt6-qtbase-6.9.1-1.fc42.x86_64/src/corelib/kernel/qobjectdefs_impl.h:461
#14 doActivate<false> (sender=0x555cc2a86e20, signal_index=3, argv=argv@entry=0x7ffdd4979420) at /usr/src/debug/qt6-qtbase-6.9.1-1.fc42.x86_64/src/corelib/kernel/qobject.cpp:4146
#15 0x00007f9cc5f5c089 in QMetaObject::activate (sender=sender@entry=0x555cc1792a50, m=m@entry=0x7f9cc64a3f00, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffdd4979420) at /usr/src/debug/qt6-qtbase-6.9.1-1.fc42.x86_64/src/corelib/kernel/qobject.cpp:4206
#16 0x00007f9cc5f74593 in QMetaObject::activate<void, QSocketDescriptor, QSocketNotifier::Type, QSocketNotifier::QPrivateSignal> (sender=0x555cc1792a50, mo=0x7f9cc64a3f00, local_signal_index=0, ret=0x0) at /usr/src/debug/qt6-qtbase-6.9.1-1.fc42.x86_64/src/corelib/kernel/qobjectdefs.h:306
#17 QSocketNotifier::activated (this=this@entry=0x555cc2a86e20, _t1=..., _t2=<optimized out>, _t3=...) at /usr/src/debug/qt6-qtbase-6.9.1-1.fc42.x86_64/redhat-linux-build/src/corelib/Core_autogen/include/moc_qsocketnotifier.cpp:161
#18 0x00007f9cc5f74d6b in QSocketNotifier::event (this=0x555cc2a86e20, e=<optimized out>) at /usr/src/debug/qt6-qtbase-6.9.1-1.fc42.x86_64/src/corelib/kernel/qsocketnotifier.cpp:327
(...trimmed)

EXPECTED RESULT
No crash.

SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.1
Kernel Version: 6.15.10-200.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 8 × Intel® Core™ i7-8559U CPU @ 2.70GHz
Memory: 16 GiB of RAM (15.5 GiB usable)
Graphics Processor: Intel® Iris® Plus Graphics 655
Manufacturer: Intel(R) Client Systems
Product Name: NUC8i7BEH
System Version: J72992-303

ADDITIONAL INFORMATION