Re: [PATCH 2/2] IB/mad: Use IDR for agent IDs

From: Jason Gunthorpe
Date: Sun Jun 10 2018 - 16:30:54 EST


On Sun, Jun 10, 2018 at 03:25:05PM +0300, Leon Romanovsky wrote:
> On Sun, Jun 10, 2018 at 03:43:05AM -0700, Matthew Wilcox wrote:
> > On Sun, Jun 10, 2018 at 09:30:28AM +0300, Leon Romanovsky wrote:
> > > 1. IBTA spec doesn't talk at all about the size of TransactionID, more
> > > on that in section "13.4.6.4 TRANSACTION ID USAGE", the specification
> > > says: "The contents of the TransactionID (TID) field are implementation-
> > > dependent. So let's don't call it mlx4 bug.
> >
> > I was loosely paraphrasing the original bug report; suggested rewording
> > of the comments gratefully accepted.
>
> Just replace "mlx4 bug" with something like "to comply with mlx4
> implementation".

Well, it is a bug. Blindly replacing the upper 8 bits of the TID in a
driver without accommodation from the core is totally, bonkers wrong.

The original concept was that the 1<<24 limit would come from the
driver and only mlx4 would have less than 1<<32, because only mlx4
does this thing..

Thanks Matt,
Jason