[dpdk-dev] vfio detection

[Burakov, Anatoly]

Hi Bruce,

> > > I have a number of NIC ports which were working correctly yesterday
> > > and are bound correctly to the igb_uio driver - and I want to keep
> > > using them through the igb_uio driver for now, not vfio. However,
> > > whenever I run a dpdk application today, I find that the vfio kernel
> > > module is getting loaded each time - even after I manually remove
> > > it, and verify that it has been removed by checking lsmod. Is this
> > > expected? If so, why are we loading the vfio driver when I just want to
> continue using igb_uio which works fine?
> >
> > Can you elaborate a bit on what do you mean by "loading vfio driver"?
> > Do you mean the vfio-pci kernel gets loaded by DPDK? I certainly
> > didn't put in any code that would automatically load that driver, and
> certainly not binding devices to it.
> 
> The kernel module called just "vfio" is constantly getting reloaded, and there
> is always a "/dev/vfio" directory, which triggers the vfio code handling every
> time I run dpdk.

I can't reproduce this.

Please note that VFIO actually consists of three drivers (on an x86 system, that is) - vfio (the core VFIO infrastructure such as containers), vfio_iommu_type1 (support for x86-style IOMMU) and vfio-pci (the generic PCI driver). I have unloaded all three and ran dpdk_nic_bind and testpmd - it worked fine and no VFIO kernel drivers were loaded as a result.

Best regards,
Anatoly Burakov
DPDK SW Engineer