From: Oliver Neukum <oneukum@suse.de>
Date: Tue, 11 May 2010 21:07:03 +0000 (-0700)
Subject: hp_accel: fix race in device removal
X-Git-Tag: firefly_0821_release~10186^2~1619
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7b7be5f379bd001c86372c2e042cb7779c4f0a06;p=firefly-linux-kernel-4.4.55.git

hp_accel: fix race in device removal

commit 06efbeb4a47b6f865e1c9d175ab9d6e90b69ae9e upstream.

The work queue has to be flushed after the device has been made
inaccessible.  The patch closes a window during which a work queue might
remain active after the device is removed and would then lead to ACPI
calls with undefined behavior.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Herrmann <morpheus.ibis@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/hwmon/hp_accel.c b/drivers/hwmon/hp_accel.c
index be475e844c2a..f16d60f0bf47 100644
--- a/drivers/hwmon/hp_accel.c
+++ b/drivers/hwmon/hp_accel.c
@@ -324,8 +324,8 @@ static int lis3lv02d_remove(struct acpi_device *device, int type)
 	lis3lv02d_joystick_disable();
 	lis3lv02d_poweroff(&lis3_dev);
 
-	flush_work(&hpled_led.work);
 	led_classdev_unregister(&hpled_led.led_classdev);
+	flush_work(&hpled_led.work);
 
 	return lis3lv02d_remove_fs(&lis3_dev);
 }