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Date: Thu, 16 Dec 2010 12:24:47 -0500
From: "J. Bruce Fields" <bfields@fieldses.org>
To: "William A. (Andy) Adamson" <androsadamson@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>,
        NFS list <linux-nfs@vger.kernel.org>
Subject: Re: NFSv4.1 callback service and UDP
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On Thu, Dec 16, 2010 at 11:19:50AM -0500, William A. (Andy) Adamson wrote:
> I note that the current NFSv4.1 back channel supports UDP. Why? Should
> we continue with UDP support?

Have you tested it?

Looks to me like in that case setup_callback_client() will pass
rpc_create() a UDP svc_xprt while requesting protocol
XPRT_TRANSPORT_BC_TCP.  Looking down through the code I'm not sure
what's going to happen.  I doubt it's good....

So, agreed, making sure we error out in the UDP case (if we don't
already) would be a good idea.

--b.