[ewg] Re: [PATCH v3] libibmad: Handle MAD redirection

[Hal Rosenstock]

On Wed, Jul 1, 2009 at 12:50 PM, Jason
Gunthorpe<jgunthorpe at obsidianresearch.com> wrote:
> On Wed, Jul 01, 2009 at 11:54:13AM -0400, Hal Rosenstock wrote:
>
>> I think it depends on the interpretation of "If redirection is not being
>> performed, this shall be set to zero." in the RedirectGID description
>> as to whether it is referring to redirection in general or just GID
>> redirection.
>
> ClassPortInfo is used for alot of things,

Of course.

> I take that to mean that
> when it is used in non-redirection contexts that RedirectGID can be 0.

I took it to mean differently as there's some conflicting text in RedirectLID.

> Clearly the only sane way this can work is if the GID is always
> filled in for the redirection case.

Why is that ? Why must the redirector provide GRH info when it's not
required for subnet local cases ?

>> Futhermore, RedirectLID can be non zero but GID redirection is still
>> being used as indicated by the RedirectLID description indicating that
>> a non zero RedirectLID will in general not be valid.
>
> The spec says if it is not zero the requester shall use it. I don't
> see an ambiguity here.

To me, the ambiguity is several lines below it where it states that
the RedirectLID might not be valid and says to obtain a PathRecord
when RedirectGID is supplied rather than relying on the RedirectLID is
non zero.

-- Hal

> Jason