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=-17.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 06D30C48BC2 for ; Mon, 28 Jun 2021 01:14:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9C7461469 for ; Mon, 28 Jun 2021 01:14:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231854AbhF1BQ1 (ORCPT ); Sun, 27 Jun 2021 21:16:27 -0400 Received: from regular1.263xmail.com ([211.150.70.195]:41392 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231726AbhF1BQ1 (ORCPT ); Sun, 27 Jun 2021 21:16:27 -0400 X-Greylist: delayed 392 seconds by postgrey-1.27 at vger.kernel.org; Sun, 27 Jun 2021 21:16:26 EDT Received: from localhost (unknown [192.168.167.235]) by regular1.263xmail.com (Postfix) with ESMTP id 4B4051CAC; Mon, 28 Jun 2021 09:07:15 +0800 (CST) X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-ADDR-CHECKED4: 1 X-SKE-CHECKED: 1 X-ABS-CHECKED: 1 X-ANTISPAM-LEVEL: 2 Received: from [10.4.23.46] (unknown [58.240.82.166]) by smtp.263.net (postfix) whith ESMTP id P5175T139827079014144S1624842434919731_; Mon, 28 Jun 2021 09:07:15 +0800 (CST) X-IP-DOMAINF: 1 X-UNIQUE-TAG: <7be08a7aac80ae91b5dc06d0e1b7a40f> X-RL-SENDER: zhanglianjie@uniontech.com X-SENDER: zhanglianjie@uniontech.com X-LOGIN-NAME: zhanglianjie@uniontech.com X-FST-TO: tangyouling@loongson.cn X-RCPT-COUNT: 4 X-SENDER-IP: 58.240.82.166 X-ATTACHMENT-NUM: 0 X-System-Flag: 0 Subject: Re: [PATCH] mm: Fix the problem of mips architecture Oops To: Thomas Bogendoerfer Cc: linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, tangyouling@loongson.cn References: <20210624032212.24769-1-zhanglianjie@uniontech.com> <20210625133909.GA2565@alpha.franken.de> From: zhanglianjie Message-ID: <37efbf00-d4c8-b830-a1b6-9f90d990f4e4@uniontech.com> Date: Mon, 28 Jun 2021 09:07:14 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20210625133909.GA2565@alpha.franken.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On 2021-06-25 21:39, Thomas Bogendoerfer wrote: > On Thu, Jun 24, 2021 at 11:22:12AM +0800, zhanglianjie wrote: >> The cause of the problem is as follows: >> 1. when cat /sys/devices/system/memory/memory0/valid_zones, >> test_pages_in_a_zone() will be called. >> 2. test_pages_in_a_zone() finds the zone according to stat_pfn = 0. >> The smallest pfn of the numa node in the mips architecture is 128, >> and the page corresponding to the previous 0~127 pfn is not >> initialized (page->flags is 0xFFFFFFFF) >> 3. The nid and zonenum obtained using page_zone(pfn_to_page(0)) are out >> of bounds in the corresponding array, >> &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)], >> access to the out-of-bounds zone member variables appear abnormal, >> resulting in Oops. >> Therefore, it is necessary to keep the page between 0 and the minimum >> pfn to prevent Oops from appearing. >> >> Signed-off-by: zhanglianjie >> --- >> arch/mips/kernel/setup.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c >> index 23a140327a0b..f1da2b2ba5e9 100644 >> --- a/arch/mips/kernel/setup.c >> +++ b/arch/mips/kernel/setup.c >> @@ -653,6 +653,8 @@ static void __init arch_mem_init(char **cmdline_p) >> */ >> memblock_set_current_limit(PFN_PHYS(max_low_pfn)); >> >> + memblock_reserve(0, PAGE_SIZE * NODE_DATA(0)->node_start_pfn); >> + > > which platform needs this ? This look it should be better fixed in > the platform memory registration code. > > Thomas. > I have a problem on the loogson platform. -- Regards, Zhang Lianjie