Re: [RFC] vsock: add multiple transports support for dgram

["Jiang Wang ." <jiang.wang@bytedance.com>]

On Tue, Apr 13, 2021 at 2:02 AM Jorgen Hansen <jhansen@vmware.com> wrote:
>
>
>
> > On 7 Apr 2021, at 20:25, Jiang Wang . <jiang.wang@bytedance.com> wrote:
> >
> > On Wed, Apr 7, 2021 at 2:51 AM Jorgen Hansen <jhansen@vmware.com> wrote:
> >>
> >>
> >>> On 6 Apr 2021, at 20:31, Jiang Wang <jiang.wang@bytedance.com> wrote:
> >>>
> >>> From: "jiang.wang" <jiang.wang@bytedance.com>
> >>>
> >>> Currently, only VMCI supports dgram sockets. To supported
> >>> nested VM use case, this patch removes transport_dgram and
> >>> uses transport_g2h and transport_h2g for dgram too.
> >>
> >> Could you provide some background for introducing this change - are you
> >> looking at introducing datagrams for a different transport? VMCI datagrams
> >> already support the nested use case,
> >
> > Yes, I am trying to introduce datagram for virtio transport. I wrote a
> > spec patch for
> > virtio dgram support and also a code patch, but the code patch is still WIP.
>
> Oh ok. Cool. I must have missed the spec patch - could you provide a reference to
> it?

Sure. here is the link:
https://lists.linuxfoundation.org/pipermail/virtualization/2021-April/053543.html

> > When I wrote this commit message, I was thinking nested VM is the same as
> > multiple transport support. But now, I realize they are different.
> > Nested VMs may use
> > the same virtualization layer(KVM on KVM), or different virtualization layers
> > (KVM on ESXi). Thanks for letting me know that VMCI already supported nested
> > use cases. I think you mean VMCI on VMCI, right?
>
> Right, only VMCI on VMCI.

Got it. thanks.

> I’ll respond to Stefano’s email for the rest of the discussion.
>
> Thanks,
> Jorgen