Re: [PATCH 1/4] PCI / ACPI: Identify external PCI devices

[Mika Westerberg]

On Thu, Nov 15, 2018 at 08:27:41PM +0100, Lukas Wunner wrote:
> On Thu, Nov 15, 2018 at 09:10:26PM +0200, Mika Westerberg wrote:
> > I was thinking we could cover all these with is_external filling them
> > based on the _DSD or some other means in the kernel.
> > 
> > We would then deal all such devices as "untrusted" by default.
> 
> Tinfoil hat on, even internal devices could be malicious.
> What's the downside of enabling the feature for everything?

Mostly performance, I think. That's the main reason we put all non
external devices to passthrough IOMMU mode.