From: "Serge E. Hallyn" Subject: Re: [RFC][PATCH 2/4] sunrpc: Use utsnamespaces Date: Tue, 6 Jan 2009 15:53:24 -0600 Message-ID: <20090106215324.GD18147@us.ibm.com> References: <20090106011314.534653345@us.ibm.com> <20090106011314.961946803@us.ibm.com> <20090106200229.GA17031@us.ibm.com> <20090106202046.GF5901@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Matt Helsley , Linux Containers , linux-nfs@vger.kernel.org, Linux Kernel Mailing List , Trond Myklebust , Chuck Lever , "Eric W. Biederman" , Linux Containers , Cedric Le Goater To: "J. Bruce Fields" Return-path: Received: from e34.co.us.ibm.com ([32.97.110.152]:38734 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751562AbZAFVxd (ORCPT ); Tue, 6 Jan 2009 16:53:33 -0500 In-Reply-To: <20090106202046.GF5901@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: Quoting J. Bruce Fields (bfields@fieldses.org): > On Tue, Jan 06, 2009 at 02:02:29PM -0600, Serge E. Hallyn wrote: > > Quoting Matt Helsley (matthltc@us.ibm.com): > > > We can often specify the UTS namespace to use when starting an RPC client. > > > However sometimes no UTS namespace is available (specifically during system > > > shutdown as the last NFS mount in a container is unmounted) so fall > > > back to the initial UTS namespace. > > > > So what happens if we take this patch and do nothing else? > > > > The only potential problem situation will be rpc requests > > made on behalf of a container in which the last task has > > exited, right? So let's say a container did an nfs mount > > and then exits, causing an nfs umount request. > > > > That umount request will now be sent with the wrong nodename. > > Does that actually cause problems, will the server use the > > nodename to try and determine the client sending the request? > > This is just the machine name in the auth_unix credential? The linux > server ignores that completely (for the purpose of auth_unix > authenication, it identifies clients only by source ip address). I > suspect other servers also ignore it, but I don't know. Thanks, that's what i was hoping... Matt, have you audited the other rpc-based services? Do any of them care? -serge