From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752934Ab2I3H7R (ORCPT ); Sun, 30 Sep 2012 03:59:17 -0400 Received: from acsinet15.oracle.com ([141.146.126.227]:20393 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752609Ab2I3H5p (ORCPT ); Sun, 30 Sep 2012 03:57:45 -0400 From: Yinghai Lu To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Jacob Shin , Tejun Heo Cc: linux-kernel@vger.kernel.org, Yinghai Lu Subject: [PATCH 09/13] x86: if kernel .text .data .bss are not marked as E820_RAM, complain and fix Date: Sun, 30 Sep 2012 00:57:20 -0700 Message-Id: <1348991844-12285-10-git-send-email-yinghai@kernel.org> X-Mailer: git-send-email 1.7.7 In-Reply-To: <1348991844-12285-1-git-send-email-yinghai@kernel.org> References: <1348991844-12285-1-git-send-email-yinghai@kernel.org> X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jacob Shin 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 Signed-off-by: Yinghai Lu Reviewed-by: Pekka Enberg --- arch/x86/kernel/setup.c | 14 ++++++++++++++ 1 files changed, 14 insertions(+), 0 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 9db2922..d3da223 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -831,6 +831,20 @@ 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()) { -- 1.7.7