Re: directing soft iWARP traffic through a secure tunnel

[Chuck Lever <chuck.lever@oracle.com>]

> On Feb 19, 2021, at 9:34 AM, Bernard Metzler <BMT@zurich.ibm.com> wrote:
> 
> -----"Tom Talpey" <tom@talpey.com> wrote: -----
> 
>> To: "Jason Gunthorpe" <jgg@ziepe.ca>, "Bernard Metzler"
>> <BMT@zurich.ibm.com>
>> From: "Tom Talpey" <tom@talpey.com>
>> Date: 02/19/2021 03:15PM
>> Cc: "Chuck Lever" <chuck.lever@oracle.com>, "linux-rdma"
>> <linux-rdma@vger.kernel.org>, "Benjamin Coddington"
>> <bcodding@redhat.com>
>> Subject: [EXTERNAL] Re: directing soft iWARP traffic through a secure
>> tunnel
>> 
>> On 2/19/2021 8:57 AM, Jason Gunthorpe wrote:
>>> On Fri, Feb 19, 2021 at 01:06:26PM +0000, Bernard Metzler wrote:
>>> 
>>>> Actually, all this GID and GUID and friends for iWARP
>>>> CM looks more like squeezing things into InfiniBand terms,
>>>> where we could just rely on plain ARP and IP
>>>> (ARP resolve interface, see if there is an RDMA device
>>>> bound to, done)... or do I miss something?
>>> 
>>> I don't know how iWarp cM works very well, it would not be
>> surprising
>>> if the gid table code has gained general rocee behaviors that are
>> not
>>> applicable to iwarp modes.
>> 
>> iWarp doesn't really need a CM, it is capable of peer-to-peer without
>> any need to assign connection and queuepair ID's. The CM
>> infrastructure
>> basically just implements a state machine to allow upper layers to
>> have
>> a consistent connection API.
> 
> Well hardware iWarp need someone to organize taking away ports
> from kernel TCP which are bound to RNIC's.
> 
>> 
>> I'm with Bernard here, forcing iWarp to use CM is a fairly unnatural
>> act. Assigning a GID/GUID is unnecessary from a protocol perspective.
>> 
>> 
>>> With Steve gone I don't think there is really anyone left that even
>>> really knows how the iWarp stuff works??
>>> 
> 
> Cleaning up the iWarp path of it might be a complex undertaking.
> I don't think going down that path solves the issue soon enough
> for NFS/RDMA folks.

We have a temporary solution for the upcoming event. There will
be more such events in the future.


> But I will spend some time trying to wrap
> my head around it...
> 
> Best,
> Bernard.

--
Chuck Lever