Long-term tests of Leap 15.4 guests running VirtualBox 7.0.4 find crashes of
the VM. If 'journalctl -f' is running on the VM, the output shows repeated
instances of the following:
Dec 18 07:36:28 suse15r2 kernel: [drm:drm_crtc_commit_wait [drm]] *ERROR*
flip_done timed out
Dec 18 07:36:28 suse15r2 kernel: [drm:drm_atomic_helper_wait_for_dependencies
[drm_kms_helper]] *ERROR* [CRTC:38:crtc-0] commit wait timed out

Testing showed that VMs running the Oracle version of the code did not have the
problem, which led to the solution.

When the kernel module vboxvideo.ko became part of the kernel, generation of
that module was disabled in the openSUSE package. Although this decision had
not previously caused problems, something in the 7.0.4 code is interacting
badly with that kernel module from 5.14.X when used with the i915 driver for
the Intel Corporation CoffeeLake-S GT2 [UHD Graphics 630] hardware. The "bug"
is causing the VM to error. There may be other types of Intel graphics devices
that error - this was the only one that was available for testing. The problem
happened on every machine with this graphics device, and is not an obscure
hardware error. On one machine with nVidia hardware using the nouveau driver,
no problems were noted. We also did not find the problem with Tumbleweed
guests. It seems that whatever causes the bug, it was fixed between kernel
5.14.X used in Leap 15.4 and kernel 6.0.X used in Tumbleweed.

Once the module vboxvideo.ko was generated as part of the
virtualbox-kmp-default package, and the new code was installed on the VM, no
further problems of this type were noted.

Outside the scope of this defect, but worth noting, all Windows 11 guests run
with the 7.0.4 guest extensions crashed. Furthermore, these crashes corrupted
the virtual disk of the guest. Oracle knows of this problem and strongly
recommends that Windows 11 guests be run with the VB 6.1.40 guest extensions.
We have not found any problems with this configuration. Whether Windows 10 is
also affected is not clear.