"host doesn't support passthrough of host PCI devices" Displayed During NIC Passthrough Configuration

Symptom

When SR-IOV NIC passthrough is configured for a VM, the message "host doesn't support passthrough of host PCI devices" is displayed.

Key Process and Cause Analysis

The system memory management unit (SMMU) or input/output memory management unit (IOMMU) must be enabled for the VM to configure NIC passthrough.

Conclusion and Solution

1. Modify the BIOS configuration.

   BIOS Option	Description	Value	Path
   Support Smmu	Enables or disables system memory management unit (SMMU).	Enabled	BIOS->Advanced->MISC Config->Support Smmu

   For details about how to access the BIOS of Kunpeng servers, see "Accessing the BIOS" in TaiShan Server BIOS Parameter Reference (Kunpeng 920 Processor).

2. Open the GRUB2 configuration file.

   vi /etc/grub2-efi.cfg

3. Press i to enter the insert mode and add the following content to the file:

   iommu.passthrough=1

   

4. Press Esc, type :wq!, and press Enter to save the file and exit.
5. Restart the server for the configuration to take effect.