Date: Tue, 15 Dec 2015 10:30:22 -0700
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Michael Wang <yun.wang@profitbricks.com>
Cc: Nicholas Krause <xerofoify@gmail.com>, dledford@redhat.com,
        sean.hefty@intel.com, hal.rosenstock@gmail.com, haggaie@mellanox.com,
        matanb@mellanox.com, doront@mellanox.com, david.ahern@oracle.com,
        erezsh@mellanox.com, linux-rdma@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND] infiniband:core:Add needed error path in
 cm_init_av_by_path
Message-ID: <20151215173022.GB25965@obsidianresearch.com>
References: <1450194724-7107-1-git-send-email-xerofoify@gmail.com>
 <5670420A.7040202@profitbricks.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <5670420A.7040202@profitbricks.com>
User-Agent: Mutt/1.5.23 (2014-03-12)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 646
Lines: 16

On Tue, Dec 15, 2015 at 05:38:34PM +0100, Michael Wang wrote:
> The hop_limit is only suggest that the package allowed to be
> routed, not have to, correct?

If the hop limit is >= 2 (?) then the GRH is mandatory. The
SM will return this information in the PathRecord if it determines a
GRH is required. The whole stack follows this protocol.

The GRH is optional for in-subnet communications.

Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/