Re: [PATCH v11 1/2] virtio: let arch advertise guest's memory access restrictions

From: Halil Pasic
Date: Mon Sep 07 2020 - 18:22:41 EST


On Mon, 7 Sep 2020 11:39:06 +0200
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:

> An architecture may restrict host access to guest memory,
> e.g. IBM s390 Secure Execution or AMD SEV.
>
> Provide a new Kconfig entry the architecture can select,
> CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, when it provides
> the arch_has_restricted_virtio_memory_access callback to advertise
> to VIRTIO common code when the architecture restricts memory access
> from the host.
>
> The common code can then fail the probe for any device where
> VIRTIO_F_ACCESS_PLATFORM is required, but not set.
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>

Reviewed-by: Halil Pasic <pasic@xxxxxxxxxxxxx>

[..]
>
> +config ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
> + bool
> + help
> + This option is selected if the architecture may need to enforce
> + VIRTIO_F_IOMMU_PLATFORM.
> +

A small nit: you use F_ACCESS_PLATFORM everywhere but here.

Regards,
Halil