From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752320AbeDDPzQ (ORCPT ); Wed, 4 Apr 2018 11:55:16 -0400 Received: from out30-133.freemail.mail.aliyun.com ([115.124.30.133]:35005 "EHLO out30-133.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752030AbeDDPzO (ORCPT ); Wed, 4 Apr 2018 11:55:14 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R251e4;CH=green;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01422;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0T-fnNOH_1522857303; Subject: Re: [RFC] prctl: Deprecate non PR_SET_MM_MAP operations To: Michal Hocko Cc: Cyrill Gorcunov , LKML , Andrey Vagin , Andrew Morton , Pavel Emelyanov , Michael Kerrisk References: <20180403223722.GA15783@uranus.lan> <48bcd917-4eb8-9da6-ec4b-e76a654695c4@linux.alibaba.com> <20180404053541.GA6312@dhcp22.suse.cz> From: Yang Shi Message-ID: <40dde421-5300-b11f-860a-cf19aea00ec9@linux.alibaba.com> Date: Wed, 4 Apr 2018 08:54:59 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180404053541.GA6312@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/3/18 10:35 PM, Michal Hocko wrote: > On Tue 03-04-18 16:15:20, Yang Shi wrote: >> >> On 4/3/18 3:37 PM, Cyrill Gorcunov wrote: >>> An ability to manipulate mm_struct fields was introduced in >>> sake of CRIU in first place. Later we provide more suitable >>> and safe operation PR_SET_MM_MAP where all fields to be modifed >>> are passed in one structure which allows us to make more detailed >>> verification. >>> >>> Still old interface remains present for compatibility reason >>> though CRIU itself already switched to PR_SET_MM_MAP on its >>> own long ago. >>> >>> Googling didn't reveal some other users of this operation >>> so I think it should be safe to issue deprecation warning >>> first time and get rid of this interface after a couple >>> of releases. >>> >>> CC: Andrey Vagin >>> CC: Andrew Morton >>> CC: Pavel Emelyanov >>> CC: Michael Kerrisk >>> CC: Yang Shi >>> CC: Michal Hocko >>> Signed-off-by: Cyrill Gorcunov >>> --- >>> Or we can simply drop it off because PR_SET_MM_MAP covers all needs, >>> and I would rather prefer to do that asap. >> Thanks for making it deprecated. I'd prefer just drop it off if nobody >> objects. The change will get soaked in linux-next for a while , we will know >> if it breaks compatibility (it sounds very unlikely). > Yeah, let's just drop it and have the patch in linux-next (via mmotm) > for 2 release cycles and see whether somebody complains. BTW, I will do my v3 on top of the patch (drop off prctl_set_mm). Yang > > You can add > Acked-by: Michal Hocko > for such a patch.