Re: [PATCH 0/5] vfio/pci: add blocklist and disable qat

Christoph Hellwig
2020-07-10T15:49:24Z

On Wed, Jul 01, 2020 at 01:42:09PM +0100, Christoph Hellwig wrote:
> On Wed, Jul 01, 2020 at 12:02:57PM +0100, Giovanni Cabiddu wrote:
> > This patchset defines a blocklist of devices in the vfio-pci module and adds
> > the current generation of Intel(R) QuickAssist devices to it as they are
> > not designed to run in an untrusted environment.
>
> How can they not be safe? If any device is not safe to assign the
> whole vfio concept has major issues that we need to fix for real instead
> of coming up with quirk lists for specific IDs.

No answer yet: how is this device able to bypass the IOMMU? Don't
we have a fundamental model flaw if a random device can bypass the
IOMMU protection? Except for an ATS bug I can't really think of a way
how a device could bypass the IOMMU, and in that case we should just
disable ATS.