Trying To Get SR-IOV To Work - No ARI Support Error

[tman222]

Hi all,

I'm trying to to get SR-IOV to work on my Proxmox host so that I can pass through virtual functions from the NIC to the guest VM's. The hardware I'm working with is more on the consumer end:

Intel i3-8100 CPU
Asus Prime H310I-Plus Motherboard
32GB RAM
Chelsio T540-SO-CR NIC

I followed the instructions here

https://pve.proxmox.com/wiki/PCI(e)_Passthrough

Everything worked well and I could see the different IOMMU groups. However, when I then try to enable VF's via the following command:

echo x > /sys/bus/pci/devices/device_id/sriov_numvfs

I get an error and the following is shown via dmesg:

cxgb4 0000:01:00.0: Parent bridge 00:01.0 doesn't support ARI; can't instantiate Virtual Functions

From the reading I've done, however, it looks like the Intel 300 Series chipset does support ARI and ACS, so I'm a bit perplexed. Does anyone have any ideas of what else I might be able to try, or could I just be out of luck because of lower end hardware that's being used? Thanks in advance for your help, I really appreciate it.

 

[MasterPhi]

From the reading I've done, however, it looks like the Intel 300 Series chipset does support ARI and ACS

Not true, unless you try some ACS override patch.

 

[tman222]

Thanks for the reply @MasterPhi - I was going by what read here on page 195:

https://www.intel.com/content/dam/w...ts/300-series-chipset-pch-datasheet-vol-1.pdf

• Single Root I/O Virtualization (SR- IOV) Capability with Access Control Services
(ACS) and Alternative Routing ID (ARI)

So is my understanding correct then that this actually doesn't work without a patch?

 

[MasterPhi]

It's only applied to PCIE ports from PCH, PCIE lanes from CPU are not supported. Only HEDT platform, Xeon W, Xeon scalable have CPU PCIE ACS support.