summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJohannes Berg <johannes.berg@intel.com>2012-07-10 19:39:02 +0200
committerJohannes Berg <johannes.berg@intel.com>2012-07-12 12:10:49 +0200
commit8e95ea49c94908cb10e698c5637d57f0fbdc796d (patch)
tree597f5817baab936980b6d888bfe695e8a40dc747
parent2a9e6c58871df77b69afffad250062853570ee23 (diff)
downloadop-kernel-dev-8e95ea49c94908cb10e698c5637d57f0fbdc796d.zip
op-kernel-dev-8e95ea49c94908cb10e698c5637d57f0fbdc796d.tar.gz
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>
-rw-r--r--net/wireless/chan.c4
-rw-r--r--net/wireless/core.h3
-rw-r--r--net/wireless/util.c11
3 files changed, 12 insertions, 6 deletions
diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 434c56b..1cc4b7c 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 eae5a25..bac97da 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 f7a0647..26f8cd3 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:
OpenPOWER on IntegriCloud