From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753042AbeDRSTQ (ORCPT ); Wed, 18 Apr 2018 14:19:16 -0400 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]:50543 "EHLO out30-130.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752077AbeDRSTP (ORCPT ); Wed, 18 Apr 2018 14:19:15 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R141e4;CH=green;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04446;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0T.QbfBl_1524075536; Subject: Re: [v4 PATCH] mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct To: Cyrill Gorcunov , Michal Hocko Cc: adobriyan@gmail.com, willy@infradead.org, mguzik@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <1523730291-109696-1-git-send-email-yang.shi@linux.alibaba.com> <20180418080555.GR17484@dhcp22.suse.cz> <20180418090217.GG19578@uranus.lan> <20180418090314.GU17484@dhcp22.suse.cz> <20180418094019.GH19578@uranus.lan> From: Yang Shi Message-ID: <2712b594-91b6-24be-e88f-012c8f844f27@linux.alibaba.com> Date: Wed, 18 Apr 2018 11:18:51 -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: <20180418094019.GH19578@uranus.lan> 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 4/18/18 2:40 AM, Cyrill Gorcunov wrote: > On Wed, Apr 18, 2018 at 11:03:14AM +0200, Michal Hocko wrote: >>>> What about something like the following? >>>> " >>>> arg_lock protects concurent updates but we still need mmap_sem for read >>>> to exclude races with do_brk. >>>> " >>>> Acked-by: Michal Hocko >>> Yes, thanks! Andrew, could you slightly update the changelog please? >> No, I meant it to be a comment in the _code_. > Ah, I see. Then small patch on top should do the trick. Will send out an incremental patch soon.