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Date:   Sun, 10 Jun 2018 14:30:27 -0600
From:   Jason Gunthorpe <jgg@mellanox.com>
To:     Leon Romanovsky <leon@kernel.org>
Cc:     Matthew Wilcox <willy@infradead.org>, hans.westgaard.ry@oracle.com,
        Doug Ledford <dledford@redhat.com>,
        Matthew Wilcox <mawilcox@microsoft.com>,
        linux-rdma@vger.kernel.org,
        =?utf-8?B?SMOla29u?= Bugge <haakon.bugge@oracle.com>,
        Parav Pandit <parav@mellanox.com>,
        Jack Morgenstein <jackm@dev.mellanox.co.il>,
        Pravin Shedge <pravin.shedge4linux@gmail.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] IB/mad: Use IDR for agent IDs
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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