Re: [PATCH v1] driver: base: Add driver filter support

From: Dan Williams
Date: Fri Aug 06 2021 - 10:36:39 EST


On Thu, Aug 5, 2021 at 10:17 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Thu, Aug 05, 2021 at 06:00:25PM -0700, Dan Williams wrote:
> > That said, per-device authorization is a little bit different than
> > per-driver trust. Driver trust is easy to reason about for a built-in
> > policy, while per-device authorization is easy for userspace to reason
> > about for "why is this device not talking to its driver?".
>
> See my other email about how the "per driver" trust is the wrong model,
> you need to stick to "per device" trust. Especially given that you are
> giving control of your kernel drivers over to third parties, you already
> trust them to do the right thing.

Andi, if the number of TDX devices is small could they grow an SPDM
over virtio channel? Then you can measure trust from the VM to the VMM
to the attestation server.