Re: [RFC 00/19] KVM: s390/crypto/vfio: guest dedicated crypto adapters

From: Cornelia Huck
Date: Mon Oct 16 2017 - 06:05:28 EST


On Fri, 13 Oct 2017 13:38:45 -0400
Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote:

> Overview:
> --------
> An adjunct processor (AP) facility is an IBM Z cryptographic facility. The
> AP facility is comprised of three AP instructions and from 1 to 256 AP
> adapter cards. The design takes advantage of the interpretive execution mode
> provided by the SIE architecture. With interpretive execution mode, the AP
> instructions executed on the guest are interpreted by the hardware. This
> allows guests direct access to AP adapter cards. The first goal of this
> patch series is to provide direct access by a KVM guest to an AP as a
> pass-through device. The second goal is to provide administrators with the
> means to configure KVM guests to grant direct access to AP facilities
> assigned to the LPAR in which the host linux system is running.
>
> To facilitate the comprehension of the design, let's present an overview of
> the AP architecture.

I have not yet looked at the patches (and I'm not sure whether I'll be
able to do so until after the KVM Forum), but I think this also needs
some explanation under Documentation/, so people can still make sense
of it in the future.