[vfio-users] passthrough not working.

[Alex Williamson]

[cc +vfio-users]

On Thu, 19 Oct 2017 14:20:09 +0200
redhat at vanvoorn.com wrote:

> On 2017-10-18 03:28, Alex Williamson wrote:
> > On Wed, 18 Oct 2017 03:10:20 +0200
> > redhat at vanvoorn.com wrote:
> >   
> >> Dear vfio-users,
> >> 
> >> I am having trouble passing through my GTX 660 with KVM.
> >> 
> >> When using SeaBIOS, I always get "device does not support requested
> >> feature x-vga". With OVMF, no matter what vbios I pass through, I get 
> >> no
> >> output.
> >> 
> >> Could you please take a look at it since I have been working on it for 
> >> a
> >> while?
> >> 
> >> With kind regards,
> >> 
> >> Peter Alias Mazhive.
> >> 
> >> Below is my specs, the exact error, and lspci info. Please let me know
> >> if you need anything else.
> >> 
> >> 
> >> ##########################
> >> fedora 26 4.13.5-200.fc26.x86_64
> >> 
> >> Mobo: ASUS: Maximus viii hero
> >> bios : 3201x64
> >> ASUS : GTX660DC2O2GD5 in the first slot  a pciex16x8
> >> 
> >> ###########################
> >> #  virt-manager error
> >> ########################
> >> 
> >> Error starting domain: internal error: qemu unexpectedly closed the
> >> monitor: 2017-10-18T00:46:08.309736Z qemu-system-x86_64: -device
> >> vfio-pci,host=01:00.0,x-vga=on,id=hostdev0,bus=pci.0,addr=0x2: vfio
> >> error: 0000:01:00.0: failed getting region info for VGA region index 
> >> 8:
> >> Invalid argument
> >> device does not support requested feature x-vga  
> > 
> > Are you using the disable_vga option of vfio-pci?
> > 
> > What does this show?
> > 
> > # cat /sys/module/vfio_pci/parameters/disable_vga
> > 
> > Fedora kernels should have the right config options to enable VGA
> > access through vfio.
> > 
> > Run rom-parser on the ROM file to make sure it has a UEFI section and
> > matches your device:
> > 
> > https://github.com/awilliam/rom-parser
> > 
> > Thanks,
> > Alex  
> 
> Thanx for your super fast reply, after your reply we have been trying to 
> set the disable vga to 1 and that got rid of the error BUT ,.. still no 
> output on the gtx. Even before installing windows10 setting the kvm 
> hidden flag and vendor id flag to the xml we get the (in)famous code43.
> So where to go from here on ??

No, I asked if disable_vga was set because that's the only way I could
figure that you were getting such an error using x-vga=on.  I was NOT
suggesting to set it, it's exclusively for using a UEFI ROM with OVMF,
and you didn't bother to run rom-parser to check the ROM.
 
> Your sugestions of reading the intel-iommu is following.
> 
> cat /sys/class/iommu/dmar*/intel-iommu/cap
> 1c0000c40660462
> d2008c40660462

This was to answer a question in a different thread, it's not even
related to your issue.