PROBLEM: Switching to multiple monitors in VMWare only shows a black screen

[Karlo Dautović]

[1.] One line summary of the problem:
Switching to multiple monitors in VMWare only shows a black screen

[2.] Full description of the problem/report:
After updating to the 5.7.* kernel, whenever I try switching
to multiple monitors, the screen turns to black, and stays that
way until I switch to a single monitor again. By downgrading the
kernel, I have pinpointed this issue to the 5.7 kernel release.
The 5.6.15 kernel doesn't have this issue, and every version of the
kernel from 5.7 has it.

In the attached dmesg output, the command buffer error that happens
at 20.856529 happens exactly when switching to multiple monitors
for the first time. Subsequent monitor switching doesn't output any
more error messages.

[3.] Keywords (i.e., modules, networking, kernel):
kernel, graphics, drivers

[4.] Kernel information
[4.1.] Kernel version (from /proc/version):
Linux version 5.7.3-arch1-1 (linux at archlinux) (gcc version 10.1.0
(GCC), GNU ld (GNU Binutils) 2.34.0) #1 SMP PREEMPT Wed, 17 Jun 2020
19:42:12 +0000

[4.2.] Kernel .config file:
Attached

[5.] Most recent kernel version which did not have the bug:
5.6.15

[8.] Environment
[8.1.] Software (add the output of the ver_linux script here)
Arch Linux, KDE 5.19.1-1
Attached ver_linux

[8.2.] Processor information (from /proc/cpuinfo):
Attached

[8.3.] Module information (from /proc/modules):
Attached

[8.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem)
Attached

[8.5.] PCI information ('lspci -vvv' as root)
Attached

[8.6.] SCSI information (from /proc/scsi/scsi)
Attached

[8.7.] Other information that might be relevant to the problem
       (please look in /proc and include all information that you
       think to be relevant):
dmesg output attached.
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