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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 97074C33C9E for ; Fri, 17 Jan 2020 22:27:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 76C292072B for ; Fri, 17 Jan 2020 22:27:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727766AbgAQW1b (ORCPT ); Fri, 17 Jan 2020 17:27:31 -0500 Received: from mga14.intel.com ([192.55.52.115]:58479 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726857AbgAQW1b (ORCPT ); Fri, 17 Jan 2020 17:27:31 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Jan 2020 14:27:30 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,331,1574150400"; d="scan'208";a="426149525" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by fmsmga006.fm.intel.com with ESMTP; 17 Jan 2020 14:27:28 -0800 Date: Sat, 18 Jan 2020 06:27:40 +0800 From: Wei Yang To: Wei Yang Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/migrate.c: also overwrite error when it is bigger than zero Message-ID: <20200117222740.GB29229@richard> Reply-To: Wei Yang References: <20200117074534.25324-1-richardw.yang@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200117074534.25324-1-richardw.yang@linux.intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 17, 2020 at 03:45:34PM +0800, Wei Yang wrote: >If we get here after successfully adding page to list, err would be >the number of pages in the list. > >Current code has two problems: > > * on success, 0 is not returned > * on error, the real error code is not returned > Well, this breaks the user interface. User would receive 1 even the migration succeed. The change is introduced by e0153fc2c760 ("mm: move_pages: return valid node id in status if the page is already on the target node"). >Signed-off-by: Wei Yang >--- > mm/migrate.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/mm/migrate.c b/mm/migrate.c >index 557da996b936..c3ef70de5876 100644 >--- a/mm/migrate.c >+++ b/mm/migrate.c >@@ -1677,7 +1677,7 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, > err1 = do_move_pages_to_node(mm, &pagelist, current_node); > if (!err1) > err1 = store_status(status, start, current_node, i - start); >- if (!err) >+ if (err >= 0) > err = err1; > out: > return err; >-- >2.17.1 -- Wei Yang Help you, Help me