PCI passthrough - VFIO and QEMU.

bunder · Bodhisattva Joined: 10 Apr 2004 Posts: 5934

I found virt-manager to be picky in the config options it allows. If you have to do something it doesn't like, you wind up using virsh edit, and using virt-manager to start/stop vms only.

dylanmc · Posted: Sun Dec 17, 2017 2:44 pm Post subject:

whitout a virt-manager I'm pretty sure I'm not able to run my qemu WM with the gpu passtrought, I think It's too hard for me

Hu · Moderator Joined: 06 Mar 2007 Posts: 21633

For what it's worth, you should not need to use virt-manager at all for GPU passthrough. With the right options, Qemu can do that even when called directly. However, finding those options without virt-manager may be more trouble than you want to undertake.

dylanmc · Posted: Sun Dec 17, 2017 6:49 pm Post subject:

With virt-manager I get those errors

dylanmc · Posted: Sun Dec 17, 2017 7:37 pm Post subject:

Solved that issue upgrating to version 1.4.3 of virt-manager

Now another problem,

Myu · Posted: Sun Dec 17, 2017 9:39 pm Post subject:

It means all the devices you're trying to passthrough from group 0 are not bound to the vfio_pci driver/not suitable for passthrough

How are your IOMMU groups looking ?

dylanmc · Posted: Sun Dec 17, 2017 10:38 pm Post subject:

Myu · Posted: Sun Dec 17, 2017 11:11 pm Post subject:

Are you on the latest BIOS (AGESA) ? I've read that v1.0.0.7 improved groupings a lot.

As it is, these groups are not great for passthrough, too much stuff in it.

Side question : Which item from group 0 are you trying to passthrough ?
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Gentoo stable with bits of ~amd64 // Xfce 4.13 + Compiz Reloaded.

dylanmc · Posted: Mon Dec 18, 2017 1:01 am Post subject:

dylanmc · Posted: Mon Dec 18, 2017 9:17 pm Post subject:

Myu · Posted: Tue Dec 19, 2017 10:51 am Post subject:

I'm not sure you'll have better luck with the 980ti group 2, still too much stuff in it but you can try to be certain.

For instance, here's my working 750 Ti groupings, there's only the VGA-compatible device and the GPU Audio chip :

dylanmc · Posted: Tue Dec 19, 2017 6:04 pm Post subject:

I will try, actually I have nothing else to do

I hope in a AGESA 1.0.0.7 soon ... now I'm thinking about that I have to buy an intel processor

Myu · Posted: Tue Dec 19, 2017 10:42 pm Post subject:

I hope that you'll get it soon, may I ask you which motherboard do you have ?

Otherwise, there's already some motherboards with AGESA v1.0.0.7 but I can imagine it's a hassle.
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Gentoo stable with bits of ~amd64 // Xfce 4.13 + Compiz Reloaded.

dylanmc · Posted: Wed Dec 20, 2017 5:51 pm Post subject:

Actually I have and MSI Tomahawk B350, buyed 2 week ago.. I have to wait, no other choices

dylanmc · Posted: Thu Dec 28, 2017 8:32 am Post subject:

Another question.

I see that

dylanmc · Posted: Thu Dec 28, 2017 4:17 pm Post subject:

I've got my initial MB back, and I decide to remount it.

It's a ASUS B350 prime plus, updated to AGESA 1071 but ...

Myu · Posted: Thu Dec 28, 2017 4:45 pm Post subject:

I'm not sure if I can help much more since it's becoming increasingly more hardware specific but there's someone with the exact same MB from the VFIO subreddit which managed to get it working apparently, maybe you can poke him/her ? : https://www.reddit.com/r/VFIO/comments/7ajpj7/cant_get_passthrough_to_work/

You can also ask directly there, there's quite a community with Ryzen boards : https://reddit.com/r/vfio
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Gentoo stable with bits of ~amd64 // Xfce 4.13 + Compiz Reloaded.

dylanmc · Posted: Thu Dec 28, 2017 10:23 pm Post subject:

Thanks.

I have read/write somethin (but I don't have understand how I have to format code in that forum) now I have to wait.

I have understood that my group 2 is passable for passtrought, but I have to boot in to the secondary VAGa card, as written here https://www.reddit.com/r/VFIO/comments/616xih/gpu_passthrough_with_msi_b350_tomahawk/
but I didn't get it works

I pass to the kernel the parameter

dylanmc · Posted: Thu Dec 28, 2017 11:36 pm Post subject:

Some good news here.

I was able to switch in the secondary VGA card, after booting up.
The system now goes in the secondart GPU.

I've passtrought the second GPU and the HDMI audio, and the emulator started, removese the messages from the previus boot from firt monitor/first GPU but eaves monitor without signal

And I don't understand why :/

The passtrougt GPU is under vfio-pci module.. damn .. I'm near but stalled for now. :/

Myu · Posted: Fri Dec 29, 2017 10:25 am Post subject:

We're slowly getting there

I see on Reddit that someone with the same MB managed to do it so there's hope !

I'm not sure I understood you last sentence though

So you isolate the 980Ti properly and are booted into Gentoo with you 710 right ?

Then you start QEMU and what happens ? You don't have signal on the screen output wired to the 980 ? Not even BIOS logo (Tianocore)

Do you still signal from you Gentoo desktop while doing that ? Or does it freeze/crash ?
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Gentoo stable with bits of ~amd64 // Xfce 4.13 + Compiz Reloaded.

dylanmc · Posted: Fri Dec 29, 2017 6:07 pm Post subject:

dylanmc · Posted: Fri Dec 29, 2017 10:25 pm Post subject:

https://www.reddit.com/r/VFIO/comments/7mpuup/asus_b350_prime_plus_and_passtrought_problems/

fingers crossed..

dylanmc · Posted: Tue Jan 09, 2018 10:35 pm Post subject:

I'm not able to solve my problems.. I've read a lot of threads, with no luck.

I'm sill very close, the GPU Passtrought works, but the virt-manager launch a black screen

szatox · Advocate Joined: 27 Aug 2013 Posts: 3136

keet · Guru Joined: 09 Sep 2008 Posts: 568

I'm not sure whether I'll be able to help at all, but I do have V.G.A. passthrough working on both Linux and Windows guests using plain qemu without virt-manager (the host is headless). The configurations do vary on several lines, not out of necessity, but simply because I worked on optimizing/cleaning the Gentoo configuration more recently than the Windows one (which I haven't booted into in over a week... but performance was great when I did last use it). Thus, please don't interpret differences between the two as necessary or even useful. I've just been lazy and not used/reconfigured Windows recently. For example, Gentoo uses U.E.F.I., but Windows uses B.I.O.S. Gentoo originally used B.I.O.S., but I converted it, and I hope to do the same with Windows, once I actually want to use it again.

Gentoo: