Arch Linux

Wodger

Member

Registered: 2020-11-30

Posts: 26

Multiseat and GPU passthrough switch

Hi All,

So I was lucky enough to get an upgrade to my main system a few months ago, and loving it. I am however hitting a roadblock.

First, The important specs:

CPU: 5900X
RAM: 64GB
GPU1: 1080Ti - carried over from old system
GPU2: 1050Ti - new card - reason for it below.
Using Arch with KDE Plasma

Old system repurposed into Ark Survival Evolved server for friends (who paid for my upgrade) and has no GPU (using intel iGPU)

I have 3 main uses for my system:

1. Gaming system - I use the 1080Ti for this, and have no issues gaming

2. 3D and modding system - Some of the modding tools I use only work on windows, so rather than dual boot, I run several VMs that I spin up as and when I need them and use GPU passthrough using the 1050Ti (before, on the old system with only the 1080Ti, I switched the linux system over to the Intel iGPU and passed though the 1080ti - used optimus manager for that and it worked a treat). With this setup, I have to assign VFIO on the 1050Ti via GRUB to enable passthough.

3. Mutliseat system for my daughter to game. With GPUs so hard to come by (especially where I am), and little cash handy, I use loginctl to assign the 1050Ti / usb sound card / KB and mouse and have my daughter game using her own login to my system.

The Problem,

If for instance my daughter is not using the seat, and I wish to use the VMs, I have to remove the rules entries in

/etc/udev/rules.d

add in the VFIO entry for the 1050Ti to GRUB, reboot then use the VMs. If my daughter then wants to game, its about face and replace entries / remove entries / reboot. I think you get the idea.

So, what I'm looking for is a way to basically disable the 1050Ti on the daughters seat, to enable me to bind it to VFIO to then use the VMs, and then re-enable when required without the editing and rebooting if its possible.

What I've tried so far:

> Found a post about putting the 1050Ti into draining / idle mode using nvidia-smi, it did release it from xorg, but it refused to bind to VFIO using

virsh nodedev-detach

> Followed a post by Bryan Steiner about GPU passthrough, which worked for me before when I was able to isolate the dGPU and use the iGPU to run the system using optimus manager, however it seems the 1050Ti is not getting completely disabled by the above

Anyone have any ideas?

Thanks

Pete