Re: X58 Virtualization w/ Linux

Paolo Bonzini
2016-06-16T07:17:27Z

On 16/06/2016 03:19, Yang Zhang wrote:
>> intel_iommu=on
>> intel_iommu=on vfio_iommu_type1.allow_unsafe_interrupts=1
>>
>> all sorts of combinations. I've verified that all of the relevant
>> modules load (vfio* kvm kvm_intel pci_stub) through dmesg. That that
>> "DMAR-IR" message is suspicious though, no? That there is some setting
>> in the kernel that disables remapping by default for my BIOS. I've seen
>> posts with working vt-d even with an i7-950. I wonder if they have the
>> C3 stepping of the northbridge. Does that sound like it might be an
>> issue?
>>
>> I can't believe that there is not some way to make this work, as it
>> works flawlessly with ESXi (which sits on top of a linux kernel, though
>> it's vmware's proprietary fork I think). If my system boots in "Plug and
>> play" mode, the BIOS configuration for non critical devices shouldn't
>> matter, right?
>
> It seems there are something wrong with vfio. Have you tried with legacy
> device pass through? It should be disabled on new distribution(like
> ubuntu 16.04) but RHEL6 may still support it.

There shouldn't be any difference. He gets a freeze with
intel_iommu=on, even before going to device assignment.

Paolo