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Intel GVT-g is broken? GPU virtualization
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Description

As far as I know everything necessary for GVT-g has been enabled 2 years ago in T6812, and all I need is to add a i915.enable_gvt=1 kernel parameter. At least according to this guide there doesn't seem to be anything missing.
But after testing on 2 different machines (Broadwell Core-M tablet and Kaby Lake desktop i5) it doesn't work, I don't have /sys/bus/pci/devices/0000:00:02.0/mdev_supported_types/ folder.
I also tried intel_iommu=igfx_off, intel_iommu=on and iommu=igfx_on as in T4420 but none of that worked.
Could anybody verify what I found or maybe point out any mistake I made?

Event Timeline

Jacek created this task.Mar 29 2020, 11:11 AM
tarkah added a subscriber: tarkah.Apr 16 2020, 5:21 PM

I just tested this and I can see the mdev_supported_types folder. Here is my setup:

❯ cat /etc/kernel/cmdline.d/80_kvmgt.conf
i915.enable_gvt=1 kvm.ignore_msrs=1

❯ cat /etc/modules-load.d/kvmgt.conf
kvmgt
vfio-iommu-type1
vfio-mdev

Make sure you run sudo clr-boot-manager update and reboot

tarkah added a comment.EditedApr 16 2020, 5:32 PM

Can you run lsmod | grep kvmgt to make sure the module is loaded? Also, run cat /proc/cmdline to make sure your cmdline arguments were added. Are there any errors if you run dmesg | grep gvt?

Jacek added a comment.Apr 16 2020, 6:49 PM

Thank you so much for your answer! What I was lacking was /etc/modules-load.d/kvmgt.conffile, which I didn't found in any documentation, maybe I missed it. Now it does work just fine.
Only peculiar thing is I still get i915 0000:00:02.0: Direct firmware load for i915/gvt/vid_0x8086_did_0x161e_rid_0x09.golden_hw_state failed with error -2 in dmesg.

Yeah I am getting that, too. Not sure if it'll cause any issues or not. I don't have this machine setup w/ a qemu guest to test out on. Hopefully it won't cause any problems!

DataDrake closed this task as Resolved.May 17 2020, 5:04 AM
DataDrake claimed this task.