From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 927E8C33CAF for ; Sun, 19 Jan 2020 05:44:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D9FD2071C for ; Sun, 19 Jan 2020 05:44:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725895AbgASFo0 (ORCPT ); Sun, 19 Jan 2020 00:44:26 -0500 Received: from out30-45.freemail.mail.aliyun.com ([115.124.30.45]:39530 "EHLO out30-45.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725809AbgASFo0 (ORCPT ); Sun, 19 Jan 2020 00:44:26 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R731e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04446;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0To4.P5C_1579412660; Received: from US-143344MP.local(mailfrom:yang.shi@linux.alibaba.com fp:SMTPD_---0To4.P5C_1579412660) by smtp.aliyun-inc.com(127.0.0.1); Sun, 19 Jan 2020 13:44:23 +0800 Subject: Re: [PATCH] mm: move_pages: fix the return value if there are not-migrated pages To: Wei Yang Cc: mhocko@suse.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org References: <1579325203-16405-1-git-send-email-yang.shi@linux.alibaba.com> <20200119023720.GD9745@richard> From: Yang Shi Message-ID: <6b4bda26-10c1-3631-3b49-293935975bae@linux.alibaba.com> Date: Sat, 18 Jan 2020 21:44:15 -0800 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: <20200119023720.GD9745@richard> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 1/18/20 6:37 PM, Wei Yang wrote: > On Sat, Jan 18, 2020 at 01:26:43PM +0800, Yang Shi wrote: >> The do_move_pages_to_node() might return > 0 value, the number of pages >> that are not migrated, then the value will be returned to userspace >> directly. But, move_pages() syscall would just return 0 or errno. So, >> we need reset the return value to 0 for such case as what pre-v4.17 did. >> >> Fixes: a49bd4d71637 ("mm, numa: rework do_pages_move") >> Cc: Michal Hocko >> Cc: Wei Yang >> Cc: [4.17+] >> Signed-off-by: Yang Shi >> --- >> mm/migrate.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/mm/migrate.c b/mm/migrate.c >> index 86873b6..3e75432 100644 >> --- a/mm/migrate.c >> +++ b/mm/migrate.c >> @@ -1659,8 +1659,11 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, >> goto out_flush; >> >> err = do_move_pages_to_node(mm, &pagelist, current_node); >> - if (err) >> + if (err) { >> + if (err > 0) >> + err = 0; >> goto out; >> + } >> if (i > start) { >> err = store_status(status, start, current_node, i - start); >> if (err) >> -- >> 1.8.3.1 > > Hey, I am afraid you missed something. There are three calls of > do_move_pages_to_node() in do_pages_move(). Why you just handle one return > value? How about the other two? A late night patch... I just simply missed those two. Thanks for catching it, will resolve in v2. >