diff options
| author | Luciano Coelho <luciano.coelho@intel.com> | 2015-02-06 11:19:05 +0300 |
|---|---|---|
| committer | Emmanuel Grumbach <emmanuel.grumbach@intel.com> | 2015-02-23 23:22:44 +0300 |
| commit | e7d3abab81bfb9cda80b7f5aa027fbf9e62a37fd (patch) | |
| tree | 822479b16ce0533bb7148bfe596f1f6743f1eb88 | |
| parent | 57bff1485096c53f943e26b1c5847f2a9dfe84db (diff) | |
| download | linux-e7d3abab81bfb9cda80b7f5aa027fbf9e62a37fd.tar.xz | |
iwlwifi: mvm: don't try to stop scans that are not running anymore
In certain conditions, mac80211 may ask us to stop a scan (scheduled
or normal) that is not running anymore. This can also happen when we
are doing a different type of scan, for instance, mac80211 can ask us
to stop a scheduled scan when we are running a normal scan, due to
some race conditions. In this case, we would stop the wrong type of
scan and leave everything everything in a wrong state.
To fix this, simply ignore scan stop requests for scans types that are
not running.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
| -rw-r--r-- | drivers/net/wireless/iwlwifi/mvm/mac80211.c | 33 |
1 files changed, 31 insertions, 2 deletions
diff --git a/drivers/net/wireless/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/iwlwifi/mvm/mac80211.c index 1ff7ec08532d..35feebfd048f 100644 --- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c +++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c @@ -2215,7 +2215,19 @@ static void iwl_mvm_mac_cancel_hw_scan(struct ieee80211_hw *hw, mutex_lock(&mvm->mutex); - iwl_mvm_cancel_scan(mvm); + /* Due to a race condition, it's possible that mac80211 asks + * us to stop a hw_scan when it's already stopped. This can + * happen, for instance, if we stopped the scan ourselves, + * called ieee80211_scan_completed() and the userspace called + * cancel scan scan before ieee80211_scan_work() could run. + * To handle that, simply return if the scan is not running. + */ + /* FIXME: for now, we ignore this race for UMAC scans, since + * they don't set the scan_status. + */ + if ((mvm->scan_status == IWL_MVM_SCAN_OS) || + (mvm->fw->ucode_capa.capa[0] & IWL_UCODE_TLV_CAPA_UMAC_SCAN)) + iwl_mvm_cancel_scan(mvm); mutex_unlock(&mvm->mutex); } @@ -2559,12 +2571,29 @@ static int iwl_mvm_mac_sched_scan_stop(struct ieee80211_hw *hw, int ret; mutex_lock(&mvm->mutex); + + /* Due to a race condition, it's possible that mac80211 asks + * us to stop a sched_scan when it's already stopped. This + * can happen, for instance, if we stopped the scan ourselves, + * called ieee80211_sched_scan_stopped() and the userspace called + * stop sched scan scan before ieee80211_sched_scan_stopped_work() + * could run. To handle this, simply return if the scan is + * not running. + */ + /* FIXME: for now, we ignore this race for UMAC scans, since + * they don't set the scan_status. + */ + if (mvm->scan_status != IWL_MVM_SCAN_SCHED && + !(mvm->fw->ucode_capa.capa[0] & IWL_UCODE_TLV_CAPA_UMAC_SCAN)) { + mutex_unlock(&mvm->mutex); + return 0; + } + ret = iwl_mvm_scan_offload_stop(mvm, false); mutex_unlock(&mvm->mutex); iwl_mvm_wait_for_async_handlers(mvm); return ret; - } static int iwl_mvm_mac_set_key(struct ieee80211_hw *hw, |