diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2012-07-10 19:39:02 +0200 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2012-07-12 12:10:49 +0200 |
| commit | 8e95ea49c94908cb10e698c5637d57f0fbdc796d (patch) | |
| tree | 597f5817baab936980b6d888bfe695e8a40dc747 /net/wireless | |
| parent | 2a9e6c58871df77b69afffad250062853570ee23 (diff) | |
| download | lwn-8e95ea49c94908cb10e698c5637d57f0fbdc796d.tar.gz lwn-8e95ea49c94908cb10e698c5637d57f0fbdc796d.zip | |
cfg80211: fix locking and lockdep complaints
To call cfg80211_get_chan_state() we need to lock
the wdev, so we need to lock the wdev_iter mutex
in cfg80211_can_use_iftype_chan(). This needs to
use nested locking for lockdep.
Also, cfg80211_get_chan_state() doesn't actually
use the rdev, so remove that completely including
the lock assertion that isn't needed.
Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/wireless')
| -rw-r--r-- | net/wireless/chan.c | 4 | ||||
| -rw-r--r-- | net/wireless/core.h | 3 | ||||
| -rw-r--r-- | net/wireless/util.c | 11 |
3 files changed, 12 insertions, 6 deletions
diff --git a/net/wireless/chan.c b/net/wireless/chan.c index 434c56b92c3c..1cc4b7cc7372 100644 --- a/net/wireless/chan.c +++ b/net/wireless/chan.c @@ -103,15 +103,13 @@ int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev, } void -cfg80211_get_chan_state(struct cfg80211_registered_device *rdev, - struct wireless_dev *wdev, +cfg80211_get_chan_state(struct wireless_dev *wdev, struct ieee80211_channel **chan, enum cfg80211_chan_mode *chanmode) { *chan = NULL; *chanmode = CHAN_MODE_UNDEFINED; - ASSERT_RDEV_LOCK(rdev); ASSERT_WDEV_LOCK(wdev); if (!netif_running(wdev->netdev)) diff --git a/net/wireless/core.h b/net/wireless/core.h index eae5a25a1691..bac97da751df 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -463,8 +463,7 @@ cfg80211_can_use_chan(struct cfg80211_registered_device *rdev, } void -cfg80211_get_chan_state(struct cfg80211_registered_device *rdev, - struct wireless_dev *wdev, +cfg80211_get_chan_state(struct wireless_dev *wdev, struct ieee80211_channel **chan, enum cfg80211_chan_mode *chanmode); diff --git a/net/wireless/util.c b/net/wireless/util.c index f7a0647bde9a..26f8cd30f712 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -1059,7 +1059,16 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev, if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype)) continue; - cfg80211_get_chan_state(rdev, wdev_iter, &ch, &chmode); + /* + * We may be holding the "wdev" mutex, but now need to lock + * wdev_iter. This is OK because once we get here wdev_iter + * is not wdev (tested above), but we need to use the nested + * locking for lockdep. + */ + mutex_lock_nested(&wdev_iter->mtx, 1); + __acquire(wdev_iter->mtx); + cfg80211_get_chan_state(wdev_iter, &ch, &chmode); + wdev_unlock(wdev_iter); switch (chmode) { case CHAN_MODE_UNDEFINED: |