[Solved]PCI Passthrough

element432 · n00b Joined: 16 Dec 2016 Posts: 61

So I have had PCI passthrough running on my system for over a month. The only real issue I have is every time I reboot my machine, sometimes my second GPU will not be bound, and wont bind, to vfio-pci. It is bound to nvidia. The only fix I found that makes it work is that if I restart my machine either once, or can be up to five times or so, it will be bound to vfio-pci. I'm just curious what could be causing this to happen randomly. Thanks for any tips!

PS. I am using open-rc.

szatox · Advocate Joined: 27 Aug 2013 Posts: 3131

Probably a race condition.
Blacklist or uninstall all other drivers for this GPU from host.

element432 · n00b Joined: 16 Dec 2016 Posts: 61

That's what I thought about doing, but they are both Nvidia gpus.

Imatimba · n00b Joined: 06 Nov 2017 Posts: 6

How are you binding it?
If you're using the conf file try adding the module option directly as a kernel parameter in your bootloader config:

element432 · n00b Joined: 16 Dec 2016 Posts: 61

I believe I tried this, but I don't remember so I'll try again once I get home haha. Thanks!

Anon-E-moose · Posted: Fri Jul 13, 2018 10:40 pm Post subject:

Are you unbinding it, before you try and rebind it to vfio?
_________________
PRIME x570-pro, 3700x, 6.1 zen kernel
gcc 13, profile 17.0 (custom bare multilib), openrc, wayland

element432 · n00b Joined: 16 Dec 2016 Posts: 61

Whenever I try to manually unbind it when it is bound to Nvidia, it just hangs and sometimes causes it to crash.

Anon-E-moose · Posted: Fri Jul 13, 2018 11:30 pm Post subject:

I have an nvidia and radeon now, so it's a little different, since I can now blacklist the radeon card.

BUT when I was using 2 nvidia cards I had to do this

echo 0000:02:00.0 > /sys/bus/pci/drivers/nouveau/unbind
echo 0000:02:00.0 > /sys/bus/pci/devices/0000:02:00.0/driver/unbind

First unbind from nouveau (should be the same if using nvidia drivers)
then unbind the device itself.

If that doesn't work, don't know what else to tell you.
_________________
PRIME x570-pro, 3700x, 6.1 zen kernel
gcc 13, profile 17.0 (custom bare multilib), openrc, wayland

element432 · n00b Joined: 16 Dec 2016 Posts: 61

I definitely didn't try unbinding from Nvidia first so I'll try that. I was almost at the point of just picking up a cheap Radeon card for the host haha.

Anon-E-moose · Posted: Sat Jul 14, 2018 12:46 am Post subject:

Radeon is definitely an easier pass through than nvidia, even if you had 2 radeon cards.
_________________
PRIME x570-pro, 3700x, 6.1 zen kernel
gcc 13, profile 17.0 (custom bare multilib), openrc, wayland

element432 · n00b Joined: 16 Dec 2016 Posts: 61

Thanks! That worked for me, may eventually change to a radeon card in the future though haha.