Re: Problem running rping over Intel adapters

[Doug Ledford <dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

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On 10/3/2012 6:02 PM, Hefty, Sean wrote:
>>>> 1) rping, on the client side, clears the conn_params for the 
>>>> newly to be attempted connection, then sets:
>>>> 
>>>> conn_param.responder_resources = 1; conn_param.initiator_depth 
>>>> = 1; conn_param.retry_count = 10;
>>> 
>>> 
>>>> 2) the qib driver enforces a maximum of 7 for retry_count.  I 
>>>> don't see anything in the spec that specifies a maximum for 
>>>> this entry, and in particular I know it doesn't call out for 7 
>>>> to mean infinite retries like it does for rnr_retry_count.
>>> 
>>> On IB, retry count is a 3-bit value.  See the CM REQ message.
>>> 
>>> The kernel rdma cm should probably check for a valid value and 
>>> reduce it
>> accordingly.
>> 
>> Then it's also fair to say that right now rping passes a known 
>> invalid value and needs fixed ;-)
> 
> For IB, but I wasn't sure about iWarp.  It doesn't look like it's 
> used there though.

I would hope it's not used on iWARP....it's running over it's
own link layer where this is neither defined nor applicable.

> If not, I'll apply a patch to rping, plus submit a fix for the
> kernel to validate the value.




-- 
Doug Ledford <dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
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