Re: [virtio-dev] Re: [RFC] Virtio RDMA

[Junji Wei <weijunji@bytedance.com>]

> On Feb 16, 2022, at 3:26 PM, Leon Romanovsky <leon@kernel.org> wrote:
> 
> On Wed, Feb 16, 2022 at 03:13:11PM +0800, Junji Wei wrote:
>> 
> 
> <...>
> 
>>>> We can't. So do you mean we can implement virtio-rdma only for IB in the future?
>>> 
>>> It's probably virtio-IB but we need to listen to others.
>> 
>> Agreed, one problem is that there might be some duplicated works.
> 
> Once it will be needed, the code can be refactored. IB and RoCE are
> different from user perspective, so combining them into one virtio-rdma
> module doesn't give too much advantage.

Yes, code would be fine. But there maybe some duplicated contents in spec.

> 
>> 
>>> 
>>>> 
>>>>>> And currently virtio-rdma doesn't have a strong dependency on
>>>>>> virtio-net (except for gid and ah stuffs). Is it OK to mix them up?
>>>>> 
>>>>> There are a bunch of hardware vendors that ship a converged Ethernet
>>>>> adapter. It simplifies the management and deployment.
>>>> 
>>>> Virtio-rdma is not depend on virtio-net, we can bind it to another ethernet device
>>>> via mac address in the future. And is it too mass to mix up two different device
>>>> in one spec?
>>> 
>>> So either should be fine, we just need to figure out which one is
>>> better. What I meant is to extend the virtio-net to be capable of
>>> converged ethernet.
>> 
>> Got it. One question is whether there will be some cases that user want
>> to use virtio-rdma binding to other types of ethernet device such as
>> passthroughed net device. In this case, we donât need a virtio-net
>> device actually.
> 
> What is the use case for this virtio-rdma? Especially in context of RXE.

Hmm... yes, we didnât find one. In passthrough case we can use RXE directly.

Thanks.