Messages in this thread Patch in this message | | | From | "Rafael J. Wysocki" <> | Subject | [PATCH -mm] i386: Do not restore reserved memory after hibernation | Date | Sun, 3 Jun 2007 00:14:25 +0200 |
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[Not urgent, needs to be tested in -mm] --- From: Rafael J. Wysocki <rjw@sisk.pl>
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 <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> --- 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 <linux/efi.h> #include <linux/pfn.h> #include <linux/uaccess.h> +#include <linux/suspend.h> #include <asm/pgtable.h> #include <asm/page.h> @@ -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__*/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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