Can't reboot linux guest on proxmox host with passtrough rx480

In my home setup I have an:

  • X99 gaming
  • i7 6800k
  • 64 gb ram
  • rx480 8gb

I run proxmox on that machine, as my home lab, and my idea is to passtrough the vga over my linux vm, in order to have a monitor plug to it, and run synergy between my linux vms and my windows notebook.
The problem is that when passing the vga, I can not reboot or turn off my guest vm, without having to reboot or power off my proxmox server.
Is there a way to sort that out, or the amd bug is not fixable?
Thanks for the help.

From what I understand, it is not fixable.

The only modern VGA option that fully works and should continue to to into the future are Nvidia Quadro(and tesla) cards. I think that every current AMD card has the reset bug, and every current geforce card only works with drivers that have the code 43 gimping. Code 43 can be worked around right now, but who knows what Nvidia might do in the next driver release.

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Is there any older grafic card that does not have that bug?
Mostly what I want to achieve is to have video output for the linux vm, and use it to work and manage things at home. For gaming I can use the notebook, that is also my windows enviorment.
Getting a quadro is not an option, argentinean economy is awfull. :confused:

I do not know, that is something that should be compiled/tested.

If you just want basic 3d and video acceleration, gt 710 is not too much, it does have code 43, but it has mature drivers, so even if nvidia breaks the workaround later, you are totally fine with the older release.

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I was watching a stream of @wendell and he said that rx480 not all of them have the bug, is there a place to check that?. I have an xfx rx480 8GB , model rx-480P8L

As an update, I ended up isntalling kde on the proxmox server, to avoid the trouble of passtrough.
For productivity works fine. I have to sort now the fact that I lose conectivity to my synergy server when I connect to a VPN.
And I’ll have to see if I can also game with this setup.
Thanks for the help.

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@Juan_Cruz_Fernandez, using KVM I was able to use vfio to disable the gpu from being picked up by the host, thus fixing the reset bug. This might be a viable option with proxmox I don’t know. Have a look at some of the vfio threads on this forum. I’d be interested to know if this works out for you.

I’ll try to take a look at it when I have sometime. In the meantime, I opted for installing kde on proxmox and experiment with steam and lutris. I already broke the desktop (but the server still works) so I’m trying to fix that. Proxmox runs kvm and qemu, so it should work, but last config I tried, the host used the card at boot, then pass it to the vm, and died after reboot. I can’t promise a quick update, my long holiday weekend is over, now back to work, and college.

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New update, took a lot of manglig with apt, but finally managed to get proxmox login working, virtual machines are working fine, and Kde screen locker and the rest of the desktop working, and been able to install steam and play killing floor for testing. Have to install something on lutris now, and see if there is a way to get gskill driver for my keyboard and mouse. Synergy 2 works, but I’m having a few problems with the keyboard layout when i changed between computers. Is a work in progress.

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It’s really hit or miss. I know my R9-290x doesn’t have the bug and all cards of it’s generation shouldn’t. But cards in the RX line and Fury line have the problem. Supposedly if you eject the card from the VM before shutting down you can start the VM back up without issues.

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New update, weird things keep happening, networking died on the machine, sorta fixed it on the desktop, but no vm has internet access. Have to keep looking a new fix, probably I’ll end up formating and installing everything from scratch, debian desktop, mesa, dxvk, steam, lutris and proxmox. If I manage to get it working properly I’ll try to make a guide about it.
New challenges will be getting keyboard and mouse drivers, and a proper software kvm setup.

we have a hardware survey that does a best effort attempt at listing unbugged cards:

https://passthroughpo.st/tpp-hardware-survey-results-now-available/

just filter it by AMD and look for the reset bug column

also, nv cards work flawlessly across the board with a few lines in your xml provided you have one that OVMF supports in the first place (kepler refresh and up)

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Thanks, I’ll give it a look, and Try 5o send my data.

if you’re running win10 pro on the guest you can also use chocolatey to force-remove the GPU before shutdown which works around the issue

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I was running linux (maui), but end up getting kde for the server, it’s my home lab, so it’s all right. Next step should be getting steam and lutris setup and creating a new partition for the games.

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