[vfio-users] physx can not work after VGA passthrough.

温学敏 Kayv at qq.com
Mon Apr 4 16:50:53 UTC 2016

sorry alex,i had pasted the wrong log.

here is the log that makes the VM work well.

and i found that valua of the video memory report error is a BUG of dxdiag tool. The ref is : https://support.microsoft.com/en-us/kb/2026022

here is correct log,this log is from /var/log/libvirt/qemu,and  I use the wrapper script to add the "x-vga=on" command ,so in libvirt log the "x-vga=on" command can not be found. 

2016-04-04 15:49:47.573+0000: starting up libvirt version:, package: 2.fc23 (Fedora Project, 2016-01-21-00:54:13, buildhw-01-nfs.phx2.fedoraproject.org), qemu version: 2.4.1 (qemu-2.4.1-7.fc23)
LC_ALL=C PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin QEMU_AUDIO_DRV=none /usr/bin/qemu-kvm.vga -name win7 -S -machine pc-i440fx-2.4,accel=kvm,usb=off,vmport=off -cpu SandyBridge,+erms,+smep,+fsgsbase,+pdpe1gb,+rdrand,+f16c,+osxsave,+dca,+pcid,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme,kvm=off -m 4096 -realtime mlock=off -smp 2,sockets=1,cores=2,threads=1 -uuid a6f3edfd-39a7-450f-b557-9ddb459f9401 -nographic -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/win7.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=localtime,driftfix=slew -global kvm-pit.lost_tick_policy=discard -no-hpet -no-shutdown -global PIIX4_PM.disable_s3=1 -global PIIX4_PM.disable_s4=1 -boot strict=on -device ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x6.0x7 -device ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x6 -device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x6.0x1 -device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x6.0x2 -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x5 -drive file=/var/lib/libvirt/images/win7.qcow2,if=none,id=drive-virtio-disk0,format=qcow2 -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -netdev tap,fd=23,id=hostnet0,vhost=on,vhostfd=24 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:41:6e:bb,bus=pci.0,addr=0x3 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -chardev spicevmc,id=charchannel0,name=vdagent -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=com.redhat.spice.0 -device usb-tablet,id=input0 -device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev spicevmc,id=charredir0,name=usbredir -device usb-redir,chardev=charredir0,id=redir0 -chardev spicevmc,id=charredir1,name=usbredir -device usb-redir,chardev=charredir1,id=redir1 -device vfio-pci,host=03:00.0,id=hostdev0,bus=pci.0,addr=0x2 -device vfio-pci,host=03:00.1,id=hostdev1,bus=pci.0,addr=0x9 -device usb-host,hostbus=2,hostaddr=8,id=hostdev2 -device usb-host,hostbus=2,hostaddr=7,id=hostdev3 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x8 -msg timestamp=on

From: Alex Williamson
Date: 2016-04-05 00:38
To: 温学敏
CC: vfio-users
Subject: Re: [vfio-users] physx can not work after VGA passthrough.
On Mon, Apr 4, 2016 at 9:13 AM, 温学敏 <Kayv at qq.com> wrote:
Hi guys:
    I was passthrough my GTX 970 on a win7_x64 and it works fine.The host is running a Fedora 23 Workstation.

    I use virt-manager 1.3.2 to create the VM,The version of Libvirt is 1.2.18,QEMU version is 2.4.1.

    But when I run the 3Dmark 11 to confirm the function and performance,I found that the physx function didn't work.

    Aslo i found that the display tab  in the "dxdiag" command shows me the video memory is just 679MB,and the GTX 970 have 4096MB.
    Can anyone tell me where is wrong?

     here is my qemu startup log:

Your log doesn't show any indication of having the GPU assigned to the VM at all.  Nor does it show any of the options necessary to make the NVIDIA driver work in a VM and you're not even running OVMF for the VM BIOS.  Have you followed any of the guides for configuring a VM for NVIDIA GeForce assignment?  Start here:


Read parts 1-4 for the preferred way to make this work, part 5 only if required.  Thanks,

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/vfio-users/attachments/20160405/0c9739c0/attachment.htm>

More information about the vfio-users mailing list