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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT 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 C8E14C43381 for ; Mon, 11 Mar 2019 20:10:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99E172064A for ; Mon, 11 Mar 2019 20:10:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552335039; bh=96fweznMXPE/vh0EMoHo+TkT1UGQCGtN3rh9Yv7tpSo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=o1u2yt0INYz32+JVw6At+aKc9Jsf1ObpomRfnbOF1uvZKYLmQ1Bb+uWL2BNbPDBgk SkKODe3u7TQP5hhnsCh68SawzGXqfEzfsM40jg/r0UPxeMDOaQpG1cX787Ye6gVaEk BaRGgYLl9t6ICs1ytIiHTBJ3vWes1/faLF4ynu0U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728733AbfCKT4b (ORCPT ); Mon, 11 Mar 2019 15:56:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:33754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728688AbfCKT42 (ORCPT ); Mon, 11 Mar 2019 15:56:28 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BEC30217D9; Mon, 11 Mar 2019 19:56:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552334187; bh=96fweznMXPE/vh0EMoHo+TkT1UGQCGtN3rh9Yv7tpSo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Leoz/kHgmSSe5RpF1YxH3yBxxFzWIXP/BguDUFaqDMXvEd8opesJkwh/sSACwEMrC OURQ7EAW4kYKWbawdjRelpXz1HOpSQG8ndLfra6oRnarIxyjOqmVbelhKIHTp1BGx9 lMqo6WbVfiSy7Qa7tdUUwYARmtmrznMtAHzbIWBw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Qian Cai , Pasha Tatashin , Mel Gorman , Yang Shi , Joonsoo Kim , Andrew Morton , Linus Torvalds , Sasha Levin , linux-mm@kvack.org Subject: [PATCH AUTOSEL 4.20 38/52] Revert "mm: use early_pfn_to_nid in page_ext_init" Date: Mon, 11 Mar 2019 15:55:02 -0400 Message-Id: <20190311195516.137772-38-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190311195516.137772-1-sashal@kernel.org> References: <20190311195516.137772-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Qian Cai [ Upstream commit 2f1ee0913ce58efe7f18fbd518bd54c598559b89 ] This reverts commit fe53ca54270a ("mm: use early_pfn_to_nid in page_ext_init"). When booting a system with "page_owner=on", start_kernel page_ext_init invoke_init_callbacks init_section_page_ext init_page_owner init_early_allocated_pages init_zones_in_node init_pages_in_zone lookup_page_ext page_to_nid The issue here is that page_to_nid() will not work since some page flags have no node information until later in page_alloc_init_late() due to DEFERRED_STRUCT_PAGE_INIT. Hence, it could trigger an out-of-bounds access with an invalid nid. UBSAN: Undefined behaviour in ./include/linux/mm.h:1104:50 index 7 is out of range for type 'zone [5]' Also, kernel will panic since flags were poisoned earlier with, CONFIG_DEBUG_VM_PGFLAGS=y CONFIG_NODE_NOT_IN_PAGE_FLAGS=n start_kernel setup_arch pagetable_init paging_init sparse_init sparse_init_nid memblock_alloc_try_nid_raw It did not handle it well in init_pages_in_zone() which ends up calling page_to_nid(). page:ffffea0004200000 is uninitialized and poisoned raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) page_owner info is not active (free page?) kernel BUG at include/linux/mm.h:990! RIP: 0010:init_page_owner+0x486/0x520 This means that assumptions behind commit fe53ca54270a ("mm: use early_pfn_to_nid in page_ext_init") are incomplete. Therefore, revert the commit for now. A proper way to move the page_owner initialization to sooner is to hook into memmap initialization. Link: http://lkml.kernel.org/r/20190115202812.75820-1-cai@lca.pw Signed-off-by: Qian Cai Acked-by: Michal Hocko Cc: Pasha Tatashin Cc: Mel Gorman Cc: Yang Shi Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- init/main.c | 3 ++- mm/page_ext.c | 4 +--- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/init/main.c b/init/main.c index ee147103ba1b..5def2b073b9c 100644 --- a/init/main.c +++ b/init/main.c @@ -695,7 +695,6 @@ asmlinkage __visible void __init start_kernel(void) initrd_start = 0; } #endif - page_ext_init(); kmemleak_init(); debug_objects_mem_init(); setup_per_cpu_pageset(); @@ -1147,6 +1146,8 @@ static noinline void __init kernel_init_freeable(void) sched_init_smp(); page_alloc_init_late(); + /* Initialize page ext after all struct pages are initialized. */ + page_ext_init(); do_basic_setup(); diff --git a/mm/page_ext.c b/mm/page_ext.c index ae44f7adbe07..8c78b8d45117 100644 --- a/mm/page_ext.c +++ b/mm/page_ext.c @@ -398,10 +398,8 @@ void __init page_ext_init(void) * We know some arch can have a nodes layout such as * -------------pfn--------------> * N0 | N1 | N2 | N0 | N1 | N2|.... - * - * Take into account DEFERRED_STRUCT_PAGE_INIT. */ - if (early_pfn_to_nid(pfn) != nid) + if (pfn_to_nid(pfn) != nid) continue; if (init_section_page_ext(pfn, nid)) goto oom; -- 2.19.1