Hi,

 

The following lines used to work before 6.3.1 upgrade.

 

    <hostdev mode='subsystem' type='pci' managed='yes'>

      <driver name='vfio'/>

      <source>

        <address domain='0x0000' bus='0x81' slot='0x0' function='0x0'/>

      </source>

    </hostdev>

 

With 6.3.1, I get server restarts as soon as I launch my Win7 VM.

 

Thanks,

Ruben

I'm afraid there's practically no information here, for us to even comment on what may or may not be wrong.  Please see Need help? Read me first!, and attach the diagnostics zip.

 

With nothing to go on, this will probably be moved to a support thread.  If it is determined there is a system defect here, then we can move it back.

This is the USB card I was trying to pass

IOMMU group 35

[RESET] 81:00.0 USB controller [0c03]: Fresco Logic FL1100 USB 3.0 Host Controller [1b73:1100] (rev 10)

 

Last line from /var/log/libvirt/qemu/Win7.log

2017-02-16T02:31:22.989230Z qemu-system-x86_64: -device vfio-pci,host=81:00.0,id=hostdev0,bus=pci.0,addr=0x6: Failed to mmap 0000:81:00.0 BAR 2. Performance may be slow

 

Once I get the error a hard reboot is required.

 

Thanks,

Ruben

Maybe something to do with QEMU 2.7.1:

https://lists.gnu.org/archive/html/qemu-discuss/2016-10/msg00023.html

 

But you are not providing requested info: diagnostics.zip file.  Hard to troubleshoot further.