Pass Thru devices in Hyper-V (IOMMU)

Hi folks
Is there some documentation around on how to pass devices, specifically GPU's, Disks and CPU's (if on an MP system).

On Linux host it's easy enough :

For Intel CPUs (VT-d) set intel_iommu=on. Since the kernel config option CONFIG_INTEL_IOMMU_DEFAULT_ON is not set by default when booting the host in Linux. You should also append the iommu=pt parameter. This will prevent Linux from touching devices which cannot be passed through.

I'm sure for AMD there's similar.

I'm messing around with HYPER-V today -- I've got a machine with 2 GPU's, 2 Physical CPU's (4 cores each) and 4 Mobo disk ports spare. I can't get the VM booted on to a "Native disk" and the 2nd monitor / GPU just seems to display what the ist one is showing - or just blank,

Using passthru if you have the hardware makes the VM about 99% as respomsive as it would be on a physical machine - It certainly does running Windows on a Linux beast.

Anybody got decent passthru work with HYPER-V with any version of VM. Using Host USB devices doesn't address the problem either since the Host still has to provide the main USB driver in the first place.

Cheers
jimbo

Although already almost 6 yeas old, this article is still one of the best about passing through devices in Hyper-V:


Kari

Kari said:

Although already almost 6 yeas old, this article is still one of the best about passing through devices in Hyper-V:

Passing through devices to Hyper-V VMs by using discrete device assignment - Scripting Blog [archived]

Summary: Learn how to attach a device from your Hyper-V host to your VM by using a new feature of Windows Server 2016. Today we have a guest blogger, Rudolf Vesely, who has blogged here on previous occasions. Here is a link to his previous posts if you would like to read them.

devblogs.microsoft.com

Kari

Click to expand...

Thanks -- still seems relevant

I must say though also KVM/QEMU has improved massively too over the years. I'm running an experimental guest W11 system with a load of hardware passed thru so its performance is nearly as good as native and the load on the Host is shown as really minimal as it should be as one of the 2 CPU's in the system have been passed thru to the Guest.

Cheers
jimbo