Alder Lake GVT-d integrated graphics passthrough

That thread is actually a really good read. Other people on slightly older cpus seem to have similar bar issues as me. A new kernel was released today that seemed to fix issues for one user. I’ll have to take a look and get back to you.
 
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Hey guys @jimjam my gpu is a UHD630 apologies if i confused things , I had heard that gvt-g had been dropped for newer gpu’s but maybe made the assumption gvt-d should still work (or not made the distinction when i posted)
I’m still interested in the thread, so good luck with finding a solution
Sorry again
 
Just another thought , as a work around have you considered running plex in an LXC container ? and mapping /dev/dri ?
(You'd need the igpu to be loaded by the host , so you'd need to undo any black listing of drivers (i915) etc . )
Iv'e tested this on a UHD630 , which works (and you can validate the gpu is been used by using intel_gpu_top part of a package you can install)
 
Just another thought , as a work around have you considered running plex in an LXC container ? and mapping /dev/dri ?
(You'd need the igpu to be loaded by the host , so you'd need to undo any black listing of drivers (i915) etc . )
Iv'e tested this on a UHD630 , which works (and you can validate the gpu is been used by using intel_gpu_top part of a package you can install)
No worries @scoobdriver , I appreciate anyone reaching out to help. I might have to try the LXC container. At one point I did try installing Plex directly on the Proxmox host to no avail. To be fair that was early on and I had much less knowledge of i915 and Proxmox.
 
Just another thought , as a work around have you considered running plex in an LXC container ? and mapping /dev/dri ?
(You'd need the igpu to be loaded by the host , so you'd need to undo any black listing of drivers (i915) etc . )
Iv'e tested this on a UHD630 , which works (and you can validate the gpu is been used by using intel_gpu_top part of a package you can install)
A quick question, you mentioned installing a package (intel_gpu_top) did you need to install anything else (I.e. intel drivers of any kind)?
 
A quick question, you mentioned installing a package (intel_gpu_top) did you need to install anything else (I.e. intel drivers of any kind)?
intel_gpu_top is part of intel-gpu-tools
you can install via apt install intel-gpu-tools

I do recall having to install linux-firmware on one guest machine I tried out , but nothing on the host . (I'm not sure sorry)
 
I have got Intel Quick Sync (i915) transcoding on the Proxmox host. Screen shot below shows 4, 1080p movies being transcoded with only 2% CPU utilization!

Quick Sync Working Small.png

A few things I have found along the way:

  1. Certain types of media will never use hardware transcoding. This was a killer for me, I happened to be testing with a file that would never use hardware transcoding. ahhhhhhhh!!!! - > https://www.reddit.com/r/PleX/comments/pou3b8/quick_sync_not_working/
    1. View attachment 35059
  2. Plex needs these libraries to use Intel Quick Sync (i915): https://github.com/intel/compute-runtime/releases
Now to get this working in a VM!
 
Congrats ! , LXC should be the most straight forward way !

intel_gpu_top will give you stats on the usage of the igpu on the host . e.g.

1646931667676.png
 
@scoobdriver I got an Ubunut LXC setup, passed through the /dev/dri device as well as the /dev/fb0 device as outlined in this thread. I also installed Plex just like on any Ubuntu server, added my network share, transferred my Plex Media Server folder to the Plex LXC and I'm now transcoding just like I was on the Proxmox host!

Thanks for all the help!
 
So passthrough works fine with Linux guests, but no one has got it working in a Windows guest, which is a shame as I was hoping to use it for CAD..
 
So passthrough works fine with Linux guests, but no one has got it working in a Windows guest, which is a shame as I was hoping to use it for CAD..
More explicitly, in my experience through this thread, it works with aa LXC (Linux Container). I have not attempted to passthrough to a Windows Virtual Machine. As you stated, I haven't seen or heard of anyone getting that to work with Alder Lake as of right now.
 
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Well, my LXC has been anything but reliable. When Plex starts transcoding with i915 it will eventually lead to a CPU hard LOCKUP, which ultimately takes the entire proxmox server down.

I went back and tried testing this on the Proxmox host, and ended up with the same result.

I have been attempting to get passthrough to work with a Virtual Machine again and have found a few things that really make a difference, but still have yet to be successful.
  1. I could not get the VM to even start to load i915 unless I used SeaBIOS and i440fx Machine Type.
    1. Note if using UEFI BIOS, you do have to turn off secure boot or self sign kernel 5.17 (at least at the time of this post)
  2. This blog has some good information, but ultimately doesn't work with a VM, maybe on bare metal it does work?
  3. I was trying to use Linux Kernel 5.17
    1. When doing this I did have to manually load firmware from here: https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/i915
  4. The Plex forums have a few threads started on i915 ADL support. In these threads, ChuckPA does mention that the crashes on i915 are related to Plex. Another user mentions that using Jellyfin has worked great for them.

@________ I did take a loot at the reddit thread and have started conversing with the user that said they have gotten it to work on Linux. Hopefully something comes of it...
 
Been following this thread for about a month now, I'm having the same issue with UHD 730 (intel 12400 cpu), can't get it to transcode on a VM.
I have to buy an extra Nvidia 1050 just for transcoding on EMBY.

After googling around and switching multiple times between ESXi and Proxmox, and multiple kernel versions later, I gave up.

It looks to me that newer processors with UHD version above 700 (not necessarily an Alder Lake) are all experiencing similar symptoms with iGPU passthrough, either error 43 on Windows or no vBios on linux VMs.
I believe they are of the same root cause, which is intel seems to be moving on from VT-d to SR-IOV, and dropping support on VT-d on consumer grade cpus (even though they are advertising VT-d)

Perhaps linux qemu is yet to adopt with newer intel cpu core designs, idk.

Some materials I've been reading:
https://community.intel.com/t5/Inte...-gen-NUC11TNHV50L/m-p/1312501/thread-id/85660
https://williamlam.com/2021/07/pass...on-11th-gen-nuc-results-in-error-code-43.html
 
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Been following this thread for about a month now, I'm having the same issue with UHD 730 (intel 12400 cpu), can't get it to transcode on a VM.
I have to buy an extra Nvidia 1050 just for transcoding on EMBY.

After googling around and switching multiple times between ESXi and Proxmox, and multiple kernel versions later, I gave up.

It looks to me that newer processors with UHD version above 700 (not necessarily an Alder Lake) are all experiencing similar symptoms with iGPU passthrough, either error 43 on Windows or no vBios on linux VMs.
I believe they are of the same root cause, which is intel seems to be moving on from VT-d to SR-IOV, and dropping support on VT-d on consumer grade cpus (even though they are advertising VT-d)

Perhaps linux qemu is yet to adopt with newer intel cpu core designs, idk.

Some materials I've been reading:
https://community.intel.com/t5/Inte...-gen-NUC11TNHV50L/m-p/1312501/thread-id/85660
https://williamlam.com/2021/07/pass...on-11th-gen-nuc-results-in-error-code-43.html
Those threads paint a pretty grim picture. I can say with Linux I did get it working for small periods of time. Ultimately full iGPU passthrough was obtained, but I think the drivers or software utilization are just a little broke still. Time will tell.
 
Those setup using vgpu mostly all end up with system hang and freeze. Just do a normal passthroug to a normal vm. Over a Nuc9 and nuc11, the igpu can be pass fine to linux or win.. but finding the proper win version to get it work is the most challenge. When it work, don't do update as always if you want a running system. For the Alder, most developper don't even have it and quite the reason the kernel as all previous new architecture are patch over time. So good to check back this fall and later to have it fully supported.
 
Oh you got the answer. Wait few months in order to have the new instruction of cpu add to kernel and so on. it's not a proxmox issues.
 

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