From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754617Ab2H2TGl (ORCPT ); Wed, 29 Aug 2012 15:06:41 -0400 Received: from db3ehsobe002.messaging.microsoft.com ([213.199.154.140]:8204 "EHLO db3outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754503Ab2H2TEd (ORCPT ); Wed, 29 Aug 2012 15:04:33 -0400 X-Forefront-Antispam-Report: CIP:163.181.249.108;KIP:(null);UIP:(null);IPV:NLI;H:ausb3twp01.amd.com;RD:none;EFVD:NLI X-SpamScore: 8 X-BigFish: VPS8(z37d4l1036lzzz1202hzz8275bh8275dhz2dh668h839hd24he5bhf0ah107ah1155h) X-WSS-ID: 0M9J6BC-01-8HS-02 X-M-MSG: From: Jacob Shin To: X86-ML CC: LKML , "H. Peter Anvin" , Yinghai Lu , Tejun Heo , Dave Young , Chao Wang , Vivek Goyal , Andreas Herrmann , Borislav Petkov , Jacob Shin Subject: [PATCH 6/6] x86: if kernel .text .data .bss are not marked as E820_RAM, complain and fix Date: Wed, 29 Aug 2012 14:04:06 -0500 Message-ID: <1346267046-6724-7-git-send-email-jacob.shin@amd.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1346267046-6724-1-git-send-email-jacob.shin@amd.com> References: <1346267046-6724-1-git-send-email-jacob.shin@amd.com> MIME-Version: 1.0 Content-Type: text/plain X-OriginatorOrg: amd.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There could be cases where user supplied memmap=exactmap memory mappings do not mark the region where the kernel .text .data and .bss reside as E820_RAM, as reported here: https://lkml.org/lkml/2012/8/14/86 Handle it by complaining, and adding the range back into the e820. Signed-off-by: Jacob Shin --- arch/x86/kernel/setup.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index a2e392e..68f82d2 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -913,6 +913,20 @@ void __init setup_arch(char **cmdline_p) insert_resource(&iomem_resource, &data_resource); insert_resource(&iomem_resource, &bss_resource); + /* + * Complain if .text .data and .bss are not marked as E820_RAM and + * attempt to fix it by adding the range. We may have a confused BIOS, + * or the user may have incorrectly supplied it via memmap=exactmap. If + * we really are running on top non-RAM, we will crash later anyways. + */ + if (!e820_all_mapped(code_resource.start, __pa(__brk_limit), E820_RAM)) { + pr_warn(".text .data .bss are not marked as E820_RAM!\n"); + + e820_add_region(code_resource.start, + __pa(__brk_limit) - code_resource.start + 1, + E820_RAM); + } + trim_bios_range(); #ifdef CONFIG_X86_32 if (ppro_with_ram_bug()) { -- 1.7.9.5