Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933160AbdCGSwC (ORCPT ); Tue, 7 Mar 2017 13:52:02 -0500 Received: from mail-wm0-f44.google.com ([74.125.82.44]:35086 "EHLO mail-wm0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751088AbdCGSv6 (ORCPT ); Tue, 7 Mar 2017 13:51:58 -0500 Subject: Re: [PATCH] blk: improve order of bio handling in generic_make_request() To: Pavel Machek References: <87h93blz6g.fsf@notabene.neil.brown.name> <71562c2c-97f4-9a0a-32ec-30e0702ca575@profitbricks.com> <87lgsjj9w8.fsf@notabene.neil.brown.name> <3f261bbe-dcec-db4b-947c-357a5b86a515@profitbricks.com> <20170307154652.GA8515@amd> Cc: NeilBrown , Jens Axboe , LKML , Lars Ellenberg , Kent Overstreet , Mike Snitzer , Mikulas Patocka From: Jack Wang Message-ID: <942d4be2-b7f0-8410-a63b-109a57f63e93@profitbricks.com> Date: Tue, 7 Mar 2017 16:53:20 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: <20170307154652.GA8515@amd> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1259 Lines: 48 On 07.03.2017 16:46, Pavel Machek wrote: > On Mon 2017-03-06 10:43:59, Jack Wang wrote: >> >> >> On 06.03.2017 05:40, NeilBrown wrote: >>> On Fri, Mar 03 2017, Jack Wang wrote: >>>> >>>> Thanks Neil for pushing the fix. >>>> >>>> We can optimize generic_make_request a little bit: >>>> - assign bio_list struct hold directly instead init and merge >>>> - remove duplicate code >>>> >>>> I think better to squash into your fix. >>> >>> Hi Jack, >>> I don't object to your changes, but I'd like to see a response from >>> Jens first. >>> My preference would be to get the original patch in, then other changes >>> that build on it, such as this one, can be added. Until the core >>> changes lands, any other work is pointless. >>> >>> Of course if Jens wants a this merged before he'll apply it, I'll >>> happily do that. >>> >>> Thanks, >>> NeilBrown >> >> Hi Neil, >> >> Totally agree, let's wait for Jens's decision. >> >> Hi Jens, >> >> Please consider this fix also for stable 4.3+ > > Stable? We don't put this into stable, with exception of minimal fixes > for real bugs... > Pavel > It indeed fixes deadlock in RAID1 case. Please follow the link I replied to Jens regarding the test. It did hit us in our production. Thanks, Jack