iwlegacy: fix channel switch locking
We use priv->mutex to avoid race conditions between chswitch_done()
and mac_channel_switch(), when marking channel switch in
progress. But chswitch_done() can be called in atomic context
from rx_csa() or with mutex already taken from commit_rxon().
To fix remove mutex from chswitch_done() and use atomic bitops
for marking channel switch pending.
Cc: stable@kernel.org # 2.6.39+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlegacy/iwl-dev.h b/drivers/net/wireless/iwlegacy/iwl-dev.h
index be0106c..ea30122 100644
--- a/drivers/net/wireless/iwlegacy/iwl-dev.h
+++ b/drivers/net/wireless/iwlegacy/iwl-dev.h
@@ -855,17 +855,6 @@
};
/*
- * iwl_switch_rxon: "channel switch" structure
- *
- * @ switch_in_progress: channel switch in progress
- * @ channel: new channel
- */
-struct iwl_switch_rxon {
- bool switch_in_progress;
- __le16 channel;
-};
-
-/*
* schedule the timer to wake up every UCODE_TRACE_PERIOD milliseconds
* to perform continuous uCode event logging operation if enabled
*/
@@ -1115,7 +1104,7 @@
struct iwl_rxon_context contexts[NUM_IWL_RXON_CTX];
- struct iwl_switch_rxon switch_rxon;
+ __le16 switch_channel;
/* 1st responses from initialize and runtime uCode images.
* _4965's initialize alive response contains some calibration data. */