GPU Passthrough Management Script for DDA (Discrete Device Assignment)

This PowerShell script (gpu-passthrough.ps1) enables administrators to manage GPU mappings for Hyper-V virtual machines (VMs) using Discrete Device Assignment (DDA). It includes functionality to discover available GPUs and VMs, map GPUs to VMs, unmap GPUs, and revert associated settings.

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Features

• Discover GPUs and VMs: Lists all available GPUs and VMs with detailed information.
• GPU-to-VM Mapping: Assigns GPUs to VMs with necessary configuration for DDA.
• GPU Unmapping: Removes GPU mappings from VMs and reverts VM configuration changes.
• IOMMU Check: Verifies if the system supports IOMMU, a prerequisite for DDA.
• Dry Run Mode: Simulates actions without making any changes.

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Requirements

1. Windows 10/11 or Windows Server 2016 and above.
2. Hyper-V must be enabled and configured.
3. PowerShell 5.1 or later.

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Script Usage

Parameters

Parameter	Description	Default Value
-action	Specifies the action to perform. Valid values: mapGPU, unmap, or leave empty for a status overview.	""
-gpuNumber	Index of the GPU to be mapped. Used with mapGPU action.	-1
-vmNumber	Index of the VM to be mapped. Used with mapGPU or unmap actions.	-1
-dryRun	Simulates the action without making any changes.	False

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Actions

1. Display Current Status

Run the script without parameters to:

• Verify IOMMU support.
• List all available GPUs and VMs.
• Display current GPU-to-VM mappings.

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.\gpu-passthrough.ps1 -action mapGPU -gpuNumber 1-vmNumber 2
Output:
[STATUS] Discovering available GPUs (including disabled)...
Available GPUs:
1. NVIDIA GeForce GTX 1080 (Status: OK)
2. AMD Radeon RX 6700 (Status: OK)
[STATUS] Discovering available Virtual Machines...
Available VMs:
1. VM1 - Status: Off
2. VM2 - Status: Running
You are about to map GPU 'NVIDIA GeForce GTX 1080' to VM 'VM2'.
Confirm? (Y/N): Y
Dismounting GPU from the host at PCIROOT(0)#PCI(0300)#PCI(0000)...
[STATUS] GPU successfully dismounted from the host.
Configuring VM 'VM2'for DDA...
[STATUS] VM memory and cache configured for DDA.
Assigning GPU to VM 'VM2'...
[STATUS] GPU 'NVIDIA GeForce GTX 1080' successfully assigned to VM 'VM2'.