From bc86863de63e6ae7ec6f9f524604631608c6cb02 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Fri, 1 Oct 2010 14:05:27 +0200 Subject: [PATCH] mac80211: perform scan cancel in hw reset work Move ieee80211_scan_cancel() and all other related code to ieee80211_restart_work() as ieee80211_restart_hw() is intended to be callable from any context. Fix a bug that RTNL lock is not taken during ieee80211_cancel_scan(). Take local->mtx before WARN(test_bit(SCAN_HW_SCANNING, &local->scanning) to prevent the race condition with __ieee80211_start_scan() described here: http://marc.info/?l=linux-wireless&m=128516716810537&w=2 Signed-off-by: Stanislaw Gruszka Signed-off-by: John W. Linville --- net/mac80211/main.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/net/mac80211/main.c b/net/mac80211/main.c index e24fa5be4264..494dba1b46a5 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -295,7 +295,17 @@ static void ieee80211_restart_work(struct work_struct *work) struct ieee80211_local *local = container_of(work, struct ieee80211_local, restart_work); + /* wait for scan work complete */ + flush_workqueue(local->workqueue); + + mutex_lock(&local->mtx); + WARN(test_bit(SCAN_HW_SCANNING, &local->scanning), + "%s called with hardware scan in progress\n", __func__); + mutex_unlock(&local->mtx); + rtnl_lock(); + if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning))) + ieee80211_scan_cancel(local); ieee80211_reconfig(local); rtnl_unlock(); } @@ -306,15 +316,6 @@ void ieee80211_restart_hw(struct ieee80211_hw *hw) trace_api_restart_hw(local); - /* wait for scan work complete */ - flush_workqueue(local->workqueue); - - WARN(test_bit(SCAN_HW_SCANNING, &local->scanning), - "%s called with hardware scan in progress\n", __func__); - - if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning))) - ieee80211_scan_cancel(local); - /* use this reason, ieee80211_reconfig will unblock it */ ieee80211_stop_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_SUSPEND); -- 2.20.1