i386: do not restore reserved memory after hibernation

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.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c
index ec4dfcc50cf7..2986b48a823f 100644
--- a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -640,6 +640,7 @@ void __init setup_arch(char **cmdline_p)
 #endif
 
         e820_register_memory();
+        e820_mark_nosave_regions();
 
 #ifdef CONFIG_VT
 #if defined(CONFIG_VGA_CONSOLE)