Merge branches 'x86-reboot-for-linus' and 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-reboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Reorder reboot method preferences

* 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, setup: Fix EDD3.0 data verification.

arch/x86/kernel/reboot.c

@@ -36,7 +36,7 @@ EXPORT_SYMBOL(pm_power_off);
 
 static const struct desc_ptr no_idt = {};
 static int reboot_mode;
-enum reboot_type reboot_type = BOOT_KBD;
+enum reboot_type reboot_type = BOOT_ACPI;
 int reboot_force;
 
 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
@@ -478,9 +478,24 @@ void __attribute__((weak)) mach_reboot_fixups(void)
 {
 }
 
+/*
+ * Windows compatible x86 hardware expects the following on reboot:
+ *
+ * 1) If the FADT has the ACPI reboot register flag set, try it
+ * 2) If still alive, write to the keyboard controller
+ * 3) If still alive, write to the ACPI reboot register again
+ * 4) If still alive, write to the keyboard controller again
+ *
+ * If the machine is still alive at this stage, it gives up. We default to
+ * following the same pattern, except that if we're still alive after (4) we'll
+ * try to force a triple fault and then cycle between hitting the keyboard
+ * controller and doing that
+ */
 static void native_machine_emergency_restart(void)
 {
 	int i;
+	int attempt = 0;
+	int orig_reboot_type = reboot_type;
 
 	if (reboot_emergency)
 		emergency_vmx_disable_all();
@@ -502,6 +517,13 @@ static void native_machine_emergency_restart(void)
 				outb(0xfe, 0x64); /* pulse reset low */
 				udelay(50);
 			}
+			if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
+				attempt = 1;
+				reboot_type = BOOT_ACPI;
+			} else {
+				reboot_type = BOOT_TRIPLE;
+			}
+			break;
 
 		case BOOT_TRIPLE:
 			load_idt(&no_idt);

drivers/firmware/edd.c

@@ -531,8 +531,8 @@ static int
 edd_has_edd30(struct edd_device *edev)
 {
 	struct edd_info *info;
-	int i, nonzero_path = 0;
-	char c;
+	int i;
+	u8 csum = 0;
 
 	if (!edev)
 		return 0;
@@ -544,16 +544,16 @@ edd_has_edd30(struct edd_device *edev)
 		return 0;
 	}
 
-	for (i = 30; i <= 73; i++) {
-		c = *(((uint8_t *) info) + i + 4);
-		if (c) {
-			nonzero_path++;
-			break;
-		}
-	}
-	if (!nonzero_path) {
+
+	/* We support only T13 spec */
+	if (info->params.device_path_info_length != 44)
+		return 0;
+
+	for (i = 30; i < info->params.device_path_info_length + 30; i++)
+		csum += *(((u8 *)&info->params) + i);
+
+	if (csum)
 		return 0;
-	}
 
 	return 1;
 }