[dpdk-dev] Having troubles binding an SR-IOV VF to uio_pci_generic on Amazon instance

[Michael S. Tsirkin]

On Thu, Oct 01, 2015 at 02:02:24PM -0700, Alexander Duyck wrote:
> validation and translation would add 10s if not 100s of nanoseconds to the
> time needed to process each packet.  In addition we are talking about doing
> this in kernel space which means we wouldn't really be able to take
> advantage of things like SSE or AVX instructions.

Yes. But the nice thing is that it's rearming so it can happen on
a separate core, in parallel with packet processing.
It does not need to add to latency.

You will burn up more CPU, but again, all this for boxes/hypervisors
without an IOMMU.

I'm sure people can come up with even better approaches, once enough
people get it that kernel absolutely needs to be protected from
userspace.

Long term, the right thing to do is to focus on IOMMU support. This
gives you hardware-based memory protection without need to burn up CPU
cycles.

-- 
MST