iwlwifi: fix possible recursive locking deadlock
commit f84b29ec0a1ab767679d3f2428877b65f94bc3ff
Author: Johannes Berg <johannes.berg@intel.com>
Date: Tue May 18 02:29:13 2010 -0700
iwlwifi: queue user-initiated scan when doing internal scan
introduced a potential deadlock because it calls
ieee80211_scan_completed() with the priv->mutex
held, but mac80211 may call back into iwlwifi
which would lead to recursive locking. Move this
out from under the mutex.
Cc: stable@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 8024d44..8ccb6d2 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -2000,6 +2000,7 @@
struct ieee80211_vif *vif)
{
struct iwl_priv *priv = hw->priv;
+ bool scan_completed = false;
IWL_DEBUG_MAC80211(priv, "enter\n");
@@ -2013,7 +2014,7 @@
if (priv->vif == vif) {
priv->vif = NULL;
if (priv->scan_vif == vif) {
- ieee80211_scan_completed(priv->hw, true);
+ scan_completed = true;
priv->scan_vif = NULL;
priv->scan_request = NULL;
}
@@ -2021,6 +2022,9 @@
}
mutex_unlock(&priv->mutex);
+ if (scan_completed)
+ ieee80211_scan_completed(priv->hw, true);
+
IWL_DEBUG_MAC80211(priv, "leave\n");
}