Re: [virtio-comment] [PATCH v1 1/2] virtio-mem: introduce VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE

[Cornelia Huck <cohuck@redhat.com>]

On Tue, Aug 17 2021, David Hildenbrand <david@redhat.com> wrote:

> On 17.08.21 10:50, Cornelia Huck wrote:
>> On Thu, Aug 12 2021, David Hildenbrand <david@redhat.com> wrote:
>>> +With VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE, the device MAY allow the CPU to
>> 
>> "If VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE has been negotiated, ..."
>> 
>
> ack
>
>>> +read memory of unplugged memory blocks inside \field{usable_region_size}.
>> 
>> A compliant driver would not read that memory, would it?
>
> Indeed. The device could decide to allow for reading, but it's pretty 
> much undefined behavior.

Maybe make it "SHOULD NOT"? Less strong than "MUST NOT", but still makes
clear that a driver reading it is pretty much doing the wrong thing.