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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 A3F01C636CA for ; Thu, 15 Jul 2021 19:12:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81CDD61417 for ; Thu, 15 Jul 2021 19:12:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243326AbhGOTPo (ORCPT ); Thu, 15 Jul 2021 15:15:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:51194 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244277AbhGOTOk (ORCPT ); Thu, 15 Jul 2021 15:14:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2FC7A613E5; Thu, 15 Jul 2021 19:10:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626376208; bh=lvvCD7LTgbBk2JIxI9izZinDD1lKzbLj21Xxw1OsM/8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0VSE1n6LxX/UgoWcw5acIwp8z6qymz2BJZkvo/29YwQcnZXoOHMp2OZ+vrEv7hTuH IrRUnx4tqhcfkIYp0lvBZItsTceaSd31yVGmWHycrYpQI/7V9ryqEPBVLwgEa3+ah+ Vl8BW3i3Q0RF6RtEa4WE6xS+VORCjUW8tFNzipxc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, zhanglianjie , Thomas Bogendoerfer , Sasha Levin Subject: [PATCH 5.13 174/266] MIPS: loongsoon64: Reserve memory below starting pfn to prevent Oops Date: Thu, 15 Jul 2021 20:38:49 +0200 Message-Id: <20210715182642.808286801@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210715182613.933608881@linuxfoundation.org> References: <20210715182613.933608881@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: zhanglianjie [ Upstream commit 6817c944430d00f71ccaa9c99ff5b0096aeb7873 ] 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 Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin --- arch/mips/loongson64/numa.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/mips/loongson64/numa.c b/arch/mips/loongson64/numa.c index fa9b4a487a47..e8e3e48c5333 100644 --- a/arch/mips/loongson64/numa.c +++ b/arch/mips/loongson64/numa.c @@ -129,6 +129,9 @@ static void __init node_mem_init(unsigned int node) if (node_end_pfn(0) >= (0xffffffff >> PAGE_SHIFT)) memblock_reserve((node_addrspace_offset | 0xfe000000), 32 << 20); + + /* Reserve pfn range 0~node[0]->node_start_pfn */ + memblock_reserve(0, PAGE_SIZE * start_pfn); } } -- 2.30.2