From: Keith Packard <keithp@keithp.com>
Date: Thu, 6 Aug 2009 22:57:54 +0000 (-0700)
Subject: ACPI: don't free non-existent backlight in acpi video module
X-Git-Tag: v2.6.31-rc9~33^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e29b3ee3b005897fbdcfdd4b3190776e38739d70;p=profile%2Fivi%2Fkernel-x86-ivi.git

ACPI: don't free non-existent backlight in acpi video module

acpi_video_put_one_device was attempting to remove sysfs entries and
unregister a backlight device without first checking that said backlight
device structure had been created.

Signed-off-by: Keith Packard <keithp@keithp.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
---

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 8851315..60ea984 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -2004,8 +2004,11 @@ static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
 	status = acpi_remove_notify_handler(device->dev->handle,
 					    ACPI_DEVICE_NOTIFY,
 					    acpi_video_device_notify);
-	sysfs_remove_link(&device->backlight->dev.kobj, "device");
-	backlight_device_unregister(device->backlight);
+	if (device->backlight) {
+		sysfs_remove_link(&device->backlight->dev.kobj, "device");
+		backlight_device_unregister(device->backlight);
+		device->backlight = NULL;
+	}
 	if (device->cdev) {
 		sysfs_remove_link(&device->dev->dev.kobj,
 				  "thermal_cooling");