Created attachment 1585050 [details]
a video evidence

Description of problem:
Remnant of mouse cursor left under the bottom right after VM first boot

Version-Release number of selected component (if applicable):
4.18.0-107.el8.x86_64(host & guest)
qemu-kvm-4.0.0-4.module+el8.1.0+3356+cda7f1ee.x86_64

How reproducible:
100%

Steps to Reproduce:
1.Boot rhel 8.1 vm with qemu cli:
/usr/libexec/qemu-kvm \
-name guest=vnc,debug-threads=on \
-S \
-object secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-2-vnc/master-key.aes \
-machine pc-q35-rhel8.0.0,accel=kvm,usb=off,dump-guest-core=off \
-cpu Opteron_G5,vme=on,x2apic=on,tsc-deadline=on,hypervisor=on,arat=on,tsc_adjust=on,bmi1=on,arch-capabilities=on,mmxext=on,fxsr_opt=on,cmp_legacy=on,cr8legacy=on,osvw=on,perfctr_core=on,ibpb=on,virt-ssbd=on,svm=off \
-m 8192 \
-overcommit mem-lock=off \
-smp 2,sockets=1,cores=2,threads=1 \
-uuid 1465b8c2-fc8b-4449-84ee-a2d63314bc6e \
-no-user-config \
-nodefaults \
-chardev socket,id=charmonitor,fd=29,server,nowait \
-mon chardev=charmonitor,id=monitor,mode=control \
-rtc base=utc,driftfix=slew \
-global kvm-pit.lost_tick_policy=delay \
-no-hpet \-no-shutdown \-global ICH9-LPC.disable_s3=1 \-global ICH9-LPC.disable_s4=1 \-boot strict=on \-device pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2 \ -device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 \-device pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 \-device pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 \-device pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4 \-device pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5 \-device pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6 \-device qemu-xhci,p2=15,p3=15,id=usb,bus=pci.2,addr=0x0 \-device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 \
-drive file=/home/virtimages/VirtualMachines/vnc.img,format=raw,if=none,id=drive-virtio-disk0 \-device virtio-blk-pci,scsi=off,bus=pci.4,addr=0x0,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
-netdev tap,fd=30,id=hostnet0,vhost=on,vhostfd=31 \
-device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:56:00:00:00:09,bus=pci.1,addr=0x0 \
-chardev file,id=charserial0,path=/mnt/tests/distribution/virt/install/guests/vnc/logs/vnc_console.log \
-device isa-serial,chardev=charserial0,id=serial0 \
-chardev pty,id=charserial1 \
-device isa-serial,chardev=charserial1,id=serial1 \
-chardev socket,id=charchannel0,fd=32,server,nowait \
-device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 \
-device usb-tablet,id=input0,bus=usb.0,port=1 \
-vnc 0.0.0.0:0 \
-device VGA,id=video0,vgamem_mb=16,bus=pcie.0,addr=0x1 \
-device virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 \
-object rng-random,id=objrng0,filename=/dev/urandom \
-device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 \
-sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \
-msg timestamp=on

2.connect to VM desktop in full screen mode(use remote-viewer with -f option, this way can make issue been observed more easily)
3.move mouse cursor at gdm login screen

Actual results:
After step 3, can see a remnant of mouse cursor will be left under the bottom right

Expected results:
No remnant of mouse cursor is left

Additional info:
After moving mouse cursor for some seconds, the remnant will disappear.