Can't pass through Radeon RX 5500

[michaelf]

Hello!

I've already asked about passing through GTX 650 here - now I've changed it to Radeon 5500 and didn't even get the result I had gotten with GTX 650:
I can add PCI Card...







...but after changing display to None and logging in to Windows 10 VM I even don't see the passed-through adapter (AMD Radeon) in Device Manager (that was the case with Nvidia).

Of cource I changed the /etc/modprobe.d/vfio.conf file accordingly and created a new VM. All checks (IOMMU, remapping...) = OK.

What am I doing wrong here???

P.S. After cancelling the early binding in vfio.conf I managed to see the adapter in Windows but with the same error 43 ((

Thank you in advance,
Michael

 

[leesteken]

Did your install vendor-reset and activate it for the GPU (after each reboot)?

 

[michaelf]

Not yet - I don't quite understant should I do it for any VGA card being passed-through (and that would be rather weid as the guides I followed did not require it) or only for some specific cards?

 

[michaelf]

P.S. I had exactly the same error (43) with NVIDIA GTX 650 card - does it mean that card also needed vendor-resetting?

I mean may be something else is causing this error ?

 

[leesteken]

Not yet - I don't quite understant should I do it for any VGA card being passed-through (and that would be rather weid as the guides I followed did not require it) or only for some specific cards?

Lots of devices don't reset properly, but for certain AMD GPUs (which are known for reset issues) you can work-around it via vendor-reset. The link that I provided lists the AMD GPUs that it works for. I expect that it will fix your problem but there are never guarantees with passthrough. Best of luck to you.

 

[michaelf]

Thank you very much for your help, leesteken! I'll give it a try!

 

[michaelf]

P.S. one more theory question, please: am I getting it right that if the pass-through is working I must be able to see the VM's output if I connect a monitor to the passed-through card (my console is connected to the built-in card)? ...just want to know how this problem (the card can't reset) is look like...

Now I sometimes do see the Windows 10' output (from VM) on the monitor attached to the Radeon - for example I see how the Windows 10 (inside the VM) is booting, can see the "Please press CTRL+ALT+DEL to log on" screen and then the monitor goes blank, sometimes booting the VM does not produce on the monitor anything from VM at all but do produce output from the console that should be visible on the monitor attached to the built-in card - is it this problem?

 

[michaelf]

The result of installing vendor-reset module (after dkms install ):


...so module is not loaded