Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ee0-f45.google.com ([74.125.83.45]:39864 "EHLO mail-ee0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752580AbaAIR1f convert rfc822-to-8bit (ORCPT ); Thu, 9 Jan 2014 12:27:35 -0500 Received: by mail-ee0-f45.google.com with SMTP id d49so1433579eek.18 for ; Thu, 09 Jan 2014 09:27:34 -0800 (PST) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\)) Subject: Re: [PATCH 4/5] NFSD/SUNRPC: Check rpc_xprt out of xs_setup_bc_tcp From: Trond Myklebust In-Reply-To: <20140109162633.GB14308@fieldses.org> Date: Thu, 9 Jan 2014 12:27:29 -0500 Cc: Kinglong Mee , Linux NFS Mailing List Message-Id: References: <52CA7862.1020203@gmail.com> <20140106184926.GC31764@fieldses.org> <24D159B0-C13D-43A6-B307-2B967E154353@primarydata.com> <20140106225346.GB3342@fieldses.org> <52CB8B79.6040907@gmail.com> <52CE7A76.3080101@gmail.com> <52CE7AE6.4010603@gmail.com> <20140109162633.GB14308@fieldses.org> To: Dr Fields James Bruce Sender: linux-nfs-owner@vger.kernel.org List-ID: On Jan 9, 2014, at 11:26, Dr Fields James Bruce wrote: > On Thu, Jan 09, 2014 at 06:33:10PM +0800, Kinglong Mee wrote: >> Besides checking rpc_xprt out of xs_setup_bc_tcp, >> increase it's reference (it's important). > > This sounds wrong to me: the presence of a backchannel can't prevent the > client's connection from going away. Instead, when the connection dies, > any associated backchannels should be immediately destroyed. Hi Bruce, The right way to deal with this is to have knfsd shut down the rpc_client when it detects the TCP disconnection event. The xprt->count shouldn?t be an issue here: it has nothing to do with the socket connection state. Cheers Trond