From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762999AbXFBWIg (ORCPT ); Sat, 2 Jun 2007 18:08:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760190AbXFBWI3 (ORCPT ); Sat, 2 Jun 2007 18:08:29 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:32819 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759400AbXFBWI3 (ORCPT ); Sat, 2 Jun 2007 18:08:29 -0400 From: "Rafael J. Wysocki" To: Andrew Morton Subject: [PATCH -mm] i386: Do not restore reserved memory after hibernation Date: Sun, 3 Jun 2007 00:14:25 +0200 User-Agent: KMail/1.9.5 Cc: Andrey Borzenkov , Nigel Cunningham , Pavel Machek , Andi Kleen , LKML MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200706030014.26343.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org [Not urgent, needs to be tested in -mm] --- From: Rafael J. Wysocki On some systems the ACPI NVS area is located in the first 1 MB of RAM and it is overwritten by the i386 code during the restore after hibernation. This confuses the ACPI platform firmware that doesn't update the AC adapter status appropriately as a result (http://bugzilla.kernel.org/show_bug.cgi?id=7995). The solution is to register the reserved memory in the first 1 MB as 'nosave', so that swsusp doesn't touch it during the restore. Also, this has been done on x86_64 for a long time now, so this patch makes the i386 restore code behave like the x86_64 one. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek --- arch/i386/kernel/e820.c | 30 ++++++++++++++++++++++++++++++ arch/i386/kernel/setup.c | 1 + include/asm-i386/e820.h | 1 + 3 files changed, 32 insertions(+) Index: linux-2.6.22-rc3/arch/i386/kernel/e820.c =================================================================== --- linux-2.6.22-rc3.orig/arch/i386/kernel/e820.c +++ linux-2.6.22-rc3/arch/i386/kernel/e820.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -320,6 +321,35 @@ static int __init request_standard_resou subsys_initcall(request_standard_resources); +/** + * e820_mark_nosave_regions - Find the ranges of physical addresses that do not + * correspond to e820 RAM areas and mark the corresponding pages as nosave for + * hibernation. + * + * This function requires the e820 map to be sorted and without any + * overlapping entries and assumes the first e820 area to be RAM. + */ +void __init e820_mark_nosave_regions(void) +{ + int i; + unsigned long pfn; + + pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size); + for (i = 1; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + + if (pfn < PFN_UP(ei->addr)) + register_nosave_region(pfn, PFN_UP(ei->addr)); + + pfn = PFN_DOWN(ei->addr + ei->size); + if (ei->type != E820_RAM) + register_nosave_region(PFN_UP(ei->addr), pfn); + + if (pfn >= max_low_pfn) + break; + } +} + void __init add_memory_region(unsigned long long start, unsigned long long size, int type) { Index: linux-2.6.22-rc3/arch/i386/kernel/setup.c =================================================================== --- linux-2.6.22-rc3.orig/arch/i386/kernel/setup.c +++ linux-2.6.22-rc3/arch/i386/kernel/setup.c @@ -648,6 +648,7 @@ void __init setup_arch(char **cmdline_p) #endif e820_register_memory(); + e820_mark_nosave_regions(); #ifdef CONFIG_VT #if defined(CONFIG_VGA_CONSOLE) Index: linux-2.6.22-rc3/include/asm-i386/e820.h =================================================================== --- linux-2.6.22-rc3.orig/include/asm-i386/e820.h +++ linux-2.6.22-rc3/include/asm-i386/e820.h @@ -44,6 +44,7 @@ extern void register_bootmem_low_pages(u extern void e820_register_memory(void); extern void limit_regions(unsigned long long size); extern void print_memory_map(char *who); +extern void e820_mark_nosave_regions(void); #endif/*!__ASSEMBLY__*/