Commit 543708be authored Jun 18, 2010 by Johannes Berg Committed by John W. Linville Jun 18, 2010

mac80211: fix sw scan bracketing



Currently, detection in hwsim and ath9k can
detect that two sw scans are in flight at the
same time, which isn't really true. It is
caused by a race condition, because the scan
complete callback is called too late, after
the lock has been dropped, so that a new scan
can be started before it is called.

It is also called too early semantically, as
it is currently called _after_ the return to
the operating channel -- it should be before
so that drivers know this is the operating
channel again.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent 8223d2f5

net/mac80211/scan.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -286,6 +286,8 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
		local->scanning = 0;
		local->scan_channel = NULL;

		drv_sw_scan_complete(local);

		/* we only have to protect scan_req and hw/sw scan */
		mutex_unlock(&local->scan_mtx);

		@@ -295,8 +297,6 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)

		ieee80211_configure_filter(local);

		drv_sw_scan_complete(local);

		ieee80211_offchannel_return(local, true);

		done: