From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-fsdevel-owner@vger.kernel.org>
Received: from us-smtp-delivery-194.mimecast.com ([63.128.21.194]:59282 "EHLO
        us-smtp-delivery-194.mimecast.com" rhost-flags-OK-OK-OK-OK)
        by vger.kernel.org with ESMTP id S1756232AbdDGQCf (ORCPT
        <rfc822;linux-fsdevel@vger.kernel.org>);
        Fri, 7 Apr 2017 12:02:35 -0400
From: Trond Myklebust <trondmy@primarydata.com>
To: "amir73il@gmail.com" <amir73il@gmail.com>
CC: "bfields@fieldses.org" <bfields@fieldses.org>,
        "viro@zeniv.linux.org.uk" <viro@zeniv.linux.org.uk>,
        "miklos@szeredi.hu" <miklos@szeredi.hu>,
        "jlayton@poochiereds.net" <jlayton@poochiereds.net>,
        "linux-unionfs@vger.kernel.org" <linux-unionfs@vger.kernel.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
Subject: Re: overlayfs NFS export
Date: Fri, 7 Apr 2017 16:02:28 +0000
Message-ID: <1491580946.12269.5.camel@primarydata.com>
References: <CAOQ4uxhpKFhksVJTgWyy5YRzunLiQjf9TTgFO_EfBSdWvBfxWg@mail.gmail.com>
         <1491577054.10609.1.camel@primarydata.com>
         <CAJfpegu5hkHM7z4UWhoNhoXBJ9ZmmA8EpAaoThxRe45cCSDeAQ@mail.gmail.com>
         <1491579981.12269.1.camel@primarydata.com>
         <CAOQ4uxg1r5yeSntm_nHb0WJqJe-v-yBsTq1TMTj_XcjZVwPiBA@mail.gmail.com>
In-Reply-To: <CAOQ4uxg1r5yeSntm_nHb0WJqJe-v-yBsTq1TMTj_XcjZVwPiBA@mail.gmail.com>
Content-Language: en-US
Content-ID: <54B85F78FCE28344B5B6C47FB2B0BD3B@namprd11.prod.outlook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: base64
Sender: linux-fsdevel-owner@vger.kernel.org
List-ID: <linux-fsdevel.vger.kernel.org>
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