rtl8187: ->brightness_set can not sleep

commit 0fde0a8cfd0ede7f310d6a681c8e5a7cb3e32406 upstream.

Fix:

BUG: sleeping function called from invalid context at kernel/workqueue.c:2547
in_atomic(): 1, irqs_disabled(): 0, pid: 629, name: wpa_supplicant
2 locks held by wpa_supplicant/629:
 #0:  (rtnl_mutex){+.+.+.}, at: [<c08b2b84>] rtnl_lock+0x14/0x20
 #1:  (&trigger->leddev_list_lock){.+.?..}, at: [<c0867f41>] led_trigger_event+0x21/0x80
Pid: 629, comm: wpa_supplicant Not tainted 3.3.0-0.rc3.git5.1.fc17.i686
Call Trace:
 [<c046a9f6>] __might_sleep+0x126/0x1d0
 [<c0457d6c>] wait_on_work+0x2c/0x1d0
 [<c045a09a>] __cancel_work_timer+0x6a/0x120
 [<c045a160>] cancel_delayed_work_sync+0x10/0x20
 [<f7dd3c22>] rtl8187_led_brightness_set+0x82/0xf0 [rtl8187]
 [<c0867f7c>] led_trigger_event+0x5c/0x80
 [<f7ff5e6d>] ieee80211_led_radio+0x1d/0x40 [mac80211]
 [<f7ff3583>] ieee80211_stop_device+0x13/0x230 [mac80211]

Removing _sync is ok, because if led_on work is currently running
it will be finished before led_off work start to perform, since
they are always queued on the same mac80211 local->workqueue.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=795176

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Acked-by: Hin-Tak Leung <htl10@users.sourceforge.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/wireless/rtl818x/rtl8187/leds.c b/drivers/net/wireless/rtl818x/rtl8187/leds.c
index 2e0de2f..c2d5b49 100644 (file)
--- a/drivers/net/wireless/rtl818x/rtl8187/leds.c
+++ b/drivers/net/wireless/rtl818x/rtl8187/leds.c
@@ -117,7 +117,7 @@ static void rtl8187_led_brightness_set(struct led_classdev *led_dev,
                        radio_on = true;
                } else if (radio_on) {
                        radio_on = false;
-                       cancel_delayed_work_sync(&priv->led_on);
+                       cancel_delayed_work(&priv->led_on);
                        ieee80211_queue_delayed_work(hw, &priv->led_off, 0);
                }
        } else if (radio_on) {