Re: [PATCH] vhost: introduce mdev based hardware backend

Jason Wang
2019-09-27T07:14:59Z

On 2019/9/27 下午12:54, Tiwei Bie wrote:
>>> +
>>> + /*
>>> + * In vhost-mdev, userspace should pass ring addresses
>>> + * in guest physical addresses when IOMMU is disabled or
>>> + * IOVAs when IOMMU is enabled.
>>> + */
>> A question here, consider we're using noiommu mode. If guest physical
>> address is passed here, how can a device use that?
>>
>> I believe you meant "host physical address" here? And it also have the
>> implication that the HPA should be continuous (e.g using hugetlbfs).
> The comment is talking about the virtual IOMMU (i.e. iotlb in vhost).
> It should be rephrased to cover the noiommu case as well. Thanks for
> spotting this.

So the question still, if GPA is passed how can it be used by the
virtio-mdev device?

Thanks