From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id 143A36B0007 for ; Wed, 18 Apr 2018 14:19:14 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id n4so1018103pgn.9 for ; Wed, 18 Apr 2018 11:19:14 -0700 (PDT) Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com. [115.124.30.133]) by mx.google.com with ESMTPS id v14si1537875pfm.198.2018.04.18.11.19.12 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 18 Apr 2018 11:19:12 -0700 (PDT) Subject: Re: [v4 PATCH] mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct 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 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: owner-linux-mm@kvack.org List-ID: 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 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.