[SOLVED] Not sure about IOMMU group isolation

[NinthWave]

I have a Xeon E3-1230V3

According to this: https://pve.proxmox.com/wiki/Pci_passthrough

To have separate IOMMU groups, your processor needs to have support for a feature called ACS (Access Control Services). Make sure you enable the corresponding setting in your BIOS for this.

All Xeon processor support them (E3,E5) excluding Xeon E3-1200.

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

It is also important that the device(s) you want to pass through are in a separate IOMMU group. This can be checked with:

# find /sys/kernel/iommu_groups/ -type l

It is okay if the device is in an IOMMU group together with its functions (e.g. a GPU with the HDMI Audio device) or with its root port or PCI(e) bridge.

Here is the ouptut:

root@pve1:~# find /sys/kernel/iommu_groups/ -type l
/sys/kernel/iommu_groups/1/devices/0000:00:01.0
/sys/kernel/iommu_groups/1/devices/0000:01:00.0
/sys/kernel/iommu_groups/1/devices/0000:00:01.1
/sys/kernel/iommu_groups/1/devices/0000:01:00.1

Here is the output:

root@pve1:~# lspci
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller (rev 06)
00:01.1 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x8 Controller (rev 06)
01:00.0 VGA compatible controller: NVIDIA Corporation GP107GL [Quadro P600] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GP107GL High Definition Audio Controller (rev a1)

So all pci four pci devices are on Group1

The VM does not boot, returning the message: kvm: -device vfio-pci,host=0000:01:00.0,id=hostpci2.0,bus=ich9-pcie-port-3,addr=0x0.0,multifunction=on: vfio 0000:01:00.0: device is already attached TASK ERROR: start failed: QEMU exited with code 1

So I am a bit confused...

Is it where I should use : "pcie_acs_override=downstream" or the is something else or I am doomed because of this E3-1230 ?

Thanks

 

[leesteken]

The VM does not boot, returning the message: kvm: -device vfio-pci,host=0000:01:00.0,id=hostpci2.0,bus=ich9-pcie-port-3,addr=0x0.0,multifunction=on: vfio 0000:01:00.0: device is already attached TASK ERROR: start failed: QEMU exited with code 1

This usually happens when you passthrough 01:00.0 and 01:00.1 and enable All Functions on both. Don't do that because they are both functions from the same device (and you don't need to passthrough PCI bridges). Passthrough only 01:00.0 with All Functions enabled. Please share your VM configuration file if this does not resolve the issue.

 

[NinthWave]

Thanks, that's my mistake.