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 @@
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");