From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755993Ab2ISJu2 (ORCPT ); Wed, 19 Sep 2012 05:50:28 -0400 Received: from natasha.panasas.com ([67.152.220.90]:47708 "EHLO natasha.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755885Ab2ISJuY (ORCPT ); Wed, 19 Sep 2012 05:50:24 -0400 Message-ID: <50599541.9080604@panasas.com> Date: Wed, 19 Sep 2012 12:49:53 +0300 From: Boaz Harrosh User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:8.0) Gecko/20111113 Thunderbird/8.0 MIME-Version: 1.0 To: "Myklebust, Trond" CC: Greg Kroah-Hartman , Ben Hutchings , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Tigran Mkrtchyan Subject: Re: [ 16/46] NFSv4.1: Remove a bogus BUG_ON() in nfs4_layoutreturn_done References: <20120912233817.662663809@linuxfoundation.org> <20120912233819.364182315@linuxfoundation.org> <1347813183.13258.286.camel@deadeye.wl.decadent.org.uk> <20120916163703.GA7871@kroah.com> <4FA345DA4F4AE44899BD2B03EEEC2FA908FC6732@SACEXCMBX04-PRD.hq.netapp.com> In-Reply-To: <4FA345DA4F4AE44899BD2B03EEEC2FA908FC6732@SACEXCMBX04-PRD.hq.netapp.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/17/2012 04:05 PM, Myklebust, Trond wrote: >> -----Original Message----- >> From: Greg Kroah-Hartman [mailto:gregkh@linuxfoundation.org] >> Sent: Sunday, September 16, 2012 12:37 PM >> To: Ben Hutchings >> Cc: Myklebust, Trond; linux-kernel@vger.kernel.org; >> stable@vger.kernel.org; Boaz Harrosh; Tigran Mkrtchyan >> Subject: Re: [ 16/46] NFSv4.1: Remove a bogus BUG_ON() in >> nfs4_layoutreturn_done >> >> On Sun, Sep 16, 2012 at 05:33:03PM +0100, Ben Hutchings wrote: >>> On Wed, 2012-09-12 at 16:39 -0700, Greg Kroah-Hartman wrote: >>>> From: Greg KH >>>> >>>> 3.0-stable review patch. If anyone has any objections, please let me >> know. >>>> >>>> ------------------ >>>> >>>> From: Trond Myklebust >>>> >>>> commit 47fbf7976e0b7d9dcdd799e2a1baba19064d9631 upstream. >>>> >>>> Ever since commit 0a57cdac3f (NFSv4.1 send layoutreturn to fence >>>> disconnected data server) we've been sending layoutreturn calls >>>> while there is potentially still outstanding I/O to the data >>>> servers. The reason we do this is to avoid races between replayed >>>> writes to the MDS and the original writes to the DS. >>>> >>>> When this happens, the BUG_ON() in nfs4_layoutreturn_done can be >>>> triggered because it assumes that we would never call layoutreturn >>>> without knowing that all I/O to the DS is finished. The fix is to >>>> remove the BUG_ON() now that the assumptions behind the test are >>>> obsolete. >>>> >>>> Reported-by: Boaz Harrosh >>>> Reported-by: Tigran Mkrtchyan >>>> Signed-off-by: Trond Myklebust >>>> Signed-off-by: Greg Kroah-Hartman >>> [...] >>> >>> The upstream commit has: >>> >>> Cc: stable@vger.kernel.org [>=3.5] >>> >>> and so I ignored it for 3.2. Is it actually needed for the earlier >>> stable series? >> >> Crud, I missed that somehow :( >> >> Trond, should I revert this in 3.0 and 3.4 stable kernels? > > Hi Greg, > > Applying it to those kernels should be unnecessary but harmless, so if you've already applied them then I'd say just keep them. > > Cheers > Trond Trond hi I do hit this with objects layout also in 3.2. I know that in files-layout it only hits post 3.5 But we've been using layout-return since 3.0 Thanks Boaz