I enabled IOMMU and rebooted, but not sure if it helps - because I have single GPU card (so I may not passthrough it as whole to guest). Here is host output after reboot:
$ inxi -Saz
System:
Kernel: 6.4.0-150600.23.30-default arch: x86_64 bits: 64 compiler: gcc v: 7.5.0
parameters: BOOT_IMAGE=/boot/vmlinuz-6.4.0-150600.23.30-default
root=UUID=8c8ec473-0e08-4178-b4a9-fbdd78bf7754 systemd.show_status=yes preempt=full
mitigations=auto security=apparmor rfkill.default_state=0 intel_iommu=on iommu=pt
Console: pty pts/2 DM: LightDM v: 1.32.0 Distro: openSUSE Leap 15.6
VM uses 2 cores and 4GB (Host has 10 cores and 32GB RAM). Tried assigning 4 cores and 16GB RAM to VM, but problem is same (many rendering artifacts).
Here is full session output from /var/log/libvirt/qemu/fed41-gnome.log
2025-01-13 16:01:15.148+0000: starting up libvirt version: 10.0.0, qemu version: 8.2.7SUSE Linux Enterprise 15, kernel: 6.4.0-150600.23.30-default, hostname: cubi.example.com
LC_ALL=C \
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin \
HOME=/var/lib/libvirt/qemu/domain-1-fed41-gnome \
XDG_DATA_HOME=/var/lib/libvirt/qemu/domain-1-fed41-gnome/.local/share \
XDG_CACHE_HOME=/var/lib/libvirt/qemu/domain-1-fed41-gnome/.cache \
XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain-1-fed41-gnome/.config \
/usr/bin/qemu-system-x86_64 \
-name guest=fed41-gnome,debug-threads=on \
-S \
-object '{"qom-type":"secret","id":"masterKey0","format":"raw","file":"/var/lib/libvirt/qemu/domain-1-fed41-gnome/master-key.aes"}' \
-machine pc-q35-8.2,usb=off,vmport=off,dump-guest-core=off,memory-backend=pc.ram,hpet=off,acpi=on \
-accel kvm \
-cpu host,migratable=on \
-m size=4194304k \
-object '{"qom-type":"memory-backend-ram","id":"pc.ram","size":4294967296}' \
-overcommit mem-lock=off \
-smp 2,sockets=2,cores=1,threads=1 \
-uuid 60e1ffb9-c0d3-4e35-9ed8-093db6a3f118 \
-no-user-config \
-nodefaults \
-chardev socket,id=charmonitor,fd=27,server=on,wait=off \
-mon chardev=charmonitor,id=monitor,mode=control \
-rtc base=utc,driftfix=slew \
-global kvm-pit.lost_tick_policy=delay \
-no-shutdown \
-global ICH9-LPC.disable_s3=1 \
-global ICH9-LPC.disable_s4=1 \
-boot strict=on \
-device '{"driver":"pcie-root-port","port":16,"chassis":1,"id":"pci.1","bus":"pcie.0","multifunction":true,"addr":"0x2"}' \
-device '{"driver":"pcie-root-port","port":17,"chassis":2,"id":"pci.2","bus":"pcie.0","addr":"0x2.0x1"}' \
-device '{"driver":"pcie-root-port","port":18,"chassis":3,"id":"pci.3","bus":"pcie.0","addr":"0x2.0x2"}' \
-device '{"driver":"pcie-root-port","port":19,"chassis":4,"id":"pci.4","bus":"pcie.0","addr":"0x2.0x3"}' \
-device '{"driver":"pcie-root-port","port":20,"chassis":5,"id":"pci.5","bus":"pcie.0","addr":"0x2.0x4"}' \
-device '{"driver":"pcie-root-port","port":21,"chassis":6,"id":"pci.6","bus":"pcie.0","addr":"0x2.0x5"}' \
-device '{"driver":"pcie-root-port","port":22,"chassis":7,"id":"pci.7","bus":"pcie.0","addr":"0x2.0x6"}' \
-device '{"driver":"pcie-root-port","port":23,"chassis":8,"id":"pci.8","bus":"pcie.0","addr":"0x2.0x7"}' \
-device '{"driver":"pcie-root-port","port":24,"chassis":9,"id":"pci.9","bus":"pcie.0","multifunction":true,"addr":"0x3"}' \
-device '{"driver":"pcie-root-port","port":25,"chassis":10,"id":"pci.10","bus":"pcie.0","addr":"0x3.0x1"}' \
-device '{"driver":"pcie-root-port","port":26,"chassis":11,"id":"pci.11","bus":"pcie.0","addr":"0x3.0x2"}' \
-device '{"driver":"pcie-root-port","port":27,"chassis":12,"id":"pci.12","bus":"pcie.0","addr":"0x3.0x3"}' \
-device '{"driver":"pcie-root-port","port":28,"chassis":13,"id":"pci.13","bus":"pcie.0","addr":"0x3.0x4"}' \
-device '{"driver":"pcie-root-port","port":29,"chassis":14,"id":"pci.14","bus":"pcie.0","addr":"0x3.0x5"}' \
-device '{"driver":"qemu-xhci","p2":15,"p3":15,"id":"usb","bus":"pci.2","addr":"0x0"}' \
-device '{"driver":"virtio-serial-pci","id":"virtio-serial0","bus":"pci.3","addr":"0x0"}' \
-blockdev '{"driver":"file","filename":"/var/lib/libvirt/images/fed41-gnome.qcow2","node-name":"libvirt-2-storage","auto-read-only":true,"discard":"unmap"}' \
-blockdev '{"node-name":"libvirt-2-format","read-only":false,"discard":"unmap","driver":"qcow2","file":"libvirt-2-storage","backing":null}' \
-device '{"driver":"virtio-blk-pci","bus":"pci.4","addr":"0x0","drive":"libvirt-2-format","id":"virtio-disk0","bootindex":1}' \
-device '{"driver":"ide-cd","bus":"ide.0","id":"sata0-0-0"}' \
-netdev '{"type":"tap","fd":"28","vhost":true,"vhostfd":"30","id":"hostnet0"}' \
-device '{"driver":"virtio-net-pci","netdev":"hostnet0","id":"net0","mac":"52:54:00:6d:fc:cf","bus":"pci.1","addr":"0x0"}' \
-chardev pty,id=charserial0 \
-device '{"driver":"isa-serial","chardev":"charserial0","id":"serial0","index":0}' \
-chardev socket,id=charchannel0,fd=26,server=on,wait=off \
-device '{"driver":"virtserialport","bus":"virtio-serial0.0","nr":1,"chardev":"charchannel0","id":"channel0","name":"org.qemu.guest_agent.0"}' \
-chardev spicevmc,id=charchannel1,name=vdagent \
-device '{"driver":"virtserialport","bus":"virtio-serial0.0","nr":2,"chardev":"charchannel1","id":"channel1","name":"com.redhat.spice.0"}' \
-device '{"driver":"usb-tablet","id":"input0","bus":"usb.0","port":"1"}' \
-audiodev '{"id":"audio1","driver":"spice"}' \
-spice port=0,disable-ticketing=on,image-compression=off,gl=on,rendernode=/dev/dri/renderD128,seamless-migration=on \
-device '{"driver":"virtio-vga-gl","id":"video0","max_outputs":1,"bus":"pcie.0","addr":"0x1"}' \
-device '{"driver":"ich9-intel-hda","id":"sound0","bus":"pcie.0","addr":"0x1b"}' \
-device '{"driver":"hda-duplex","id":"sound0-codec0","bus":"sound0.0","cad":0,"audiodev":"audio1"}' \
-global ICH9-LPC.noreboot=off \
-watchdog-action reset \
-chardev spicevmc,id=charredir0,name=usbredir \
-device '{"driver":"usb-redir","chardev":"charredir0","id":"redir0","bus":"usb.0","port":"2"}' \
-chardev spicevmc,id=charredir1,name=usbredir \
-device '{"driver":"usb-redir","chardev":"charredir1","id":"redir1","bus":"usb.0","port":"3"}' \
-device '{"driver":"virtio-balloon-pci","id":"balloon0","bus":"pci.5","addr":"0x0"}' \
-object '{"qom-type":"rng-random","id":"objrng0","filename":"/dev/urandom"}' \
-device '{"driver":"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
char device redirected to /dev/pts/1 (label charserial0)
gl_version 46 - core profile enabled
vrend_renderer_fill_caps: Entering with stale GL error: 1280
GLSL feature level 460
2025-01-13T16:03:26.650495Z qemu-system-x86_64: terminating on signal 15 from pid 1352 (/usr/sbin/virtqemud)
2025-01-13 16:03:26.966+0000: shutting down, reason=shutdown
There are some strange GL messages at the end - not sure how important.
And output of virsh dumpxml fed41-gnome
<domain type='kvm'>
<name>fed41-gnome</name>
<uuid>60e1ffb9-c0d3-4e35-9ed8-093db6a3f118</uuid>
<metadata>
<libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0">
<libosinfo:os id="http://fedoraproject.org/fedora/unknown"/>
</libosinfo:libosinfo>
</metadata>
<memory unit='KiB'>4194304</memory>
<currentMemory unit='KiB'>4194304</currentMemory>
<vcpu placement='static'>2</vcpu>
<os>
<type arch='x86_64' machine='pc-q35-8.2'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
<vmport state='off'/>
</features>
<cpu mode='host-passthrough' check='none' migratable='on'/>
<clock offset='utc'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<pm>
<suspend-to-mem enabled='no'/>
<suspend-to-disk enabled='no'/>
</pm>
<devices>
<emulator>/usr/bin/qemu-system-x86_64</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2' discard='unmap'/>
<source file='/var/lib/libvirt/images/fed41-gnome.qcow2'/>
<target dev='vda' bus='virtio'/>
<address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<target dev='sda' bus='sata'/>
<readonly/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
<controller type='usb' index='0' model='qemu-xhci' ports='15'>
<address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
</controller>
<controller type='pci' index='0' model='pcie-root'/>
<controller type='pci' index='1' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='1' port='0x10'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='2' port='0x11'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x1'/>
</controller>
<controller type='pci' index='3' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='3' port='0x12'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x2'/>
</controller>
<controller type='pci' index='4' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='4' port='0x13'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x3'/>
</controller>
<controller type='pci' index='5' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='5' port='0x14'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x4'/>
</controller>
<controller type='pci' index='6' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='6' port='0x15'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x5'/>
</controller>
<controller type='pci' index='7' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='7' port='0x16'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x6'/>
</controller>
<controller type='pci' index='8' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='8' port='0x17'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x7'/>
</controller>
<controller type='pci' index='9' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='9' port='0x18'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='10' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='10' port='0x19'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x1'/>
</controller>
<controller type='pci' index='11' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='11' port='0x1a'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x2'/>
</controller>
<controller type='pci' index='12' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='12' port='0x1b'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x3'/>
</controller>
<controller type='pci' index='13' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='13' port='0x1c'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x4'/>
</controller>
<controller type='pci' index='14' model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='14' port='0x1d'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x5'/>
</controller>
<controller type='sata' index='0'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
</controller>
<controller type='virtio-serial' index='0'>
<address type='pci' domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
</controller>
<interface type='network'>
<mac address='52:54:00:6d:fc:cf'/>
<source network='default'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
</interface>
<serial type='pty'>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
<channel type='unix'>
<target type='virtio' name='org.qemu.guest_agent.0'/>
<address type='virtio-serial' controller='0' bus='0' port='1'/>
</channel>
<channel type='spicevmc'>
<target type='virtio' name='com.redhat.spice.0'/>
<address type='virtio-serial' controller='0' bus='0' port='2'/>
</channel>
<input type='tablet' bus='usb'>
<address type='usb' bus='0' port='1'/>
</input>
<input type='mouse' bus='ps2'/>
<input type='keyboard' bus='ps2'/>
<graphics type='spice'>
<listen type='none'/>
<image compression='off'/>
<gl enable='yes'/>
</graphics>
<sound model='ich9'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1b' function='0x0'/>
</sound>
<audio id='1' type='spice'/>
<video>
<model type='virtio' heads='1' primary='yes'>
<acceleration accel3d='yes'/>
</model>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
</video>
<redirdev bus='usb' type='spicevmc'>
<address type='usb' bus='0' port='2'/>
</redirdev>
<redirdev bus='usb' type='spicevmc'>
<address type='usb' bus='0' port='3'/>
</redirdev>
<watchdog model='itco' action='reset'/>
<memballoon model='virtio'>
<address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
</memballoon>
<rng model='virtio'>
<backend model='random'>/dev/urandom</backend>
<address type='pci' domain='0x0000' bus='0x06' slot='0x00' function='0x0'/>
</rng>
</devices>
</domain>
My main issue with Virtio GL is currently correctness (there are many unwanted rendering artifacts that make it unusable).
