From: Johannes Berg Subject: mac80211: fix todo lock The key todo lock can be taken from different locks that require it to be _bh to avoid lock inversion due to (soft)irqs. This should fix the two problems reported by Bob and Gabor: http://mid.gmane.org/20090619113049.GB18956@hash.localnet http://mid.gmane.org/4A3FA376.8020307@openwrt.org Signed-off-by: Johannes Berg Cc: Bob Copeland Cc: Gabor Juhos --- net/mac80211/key.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -70,6 +70,8 @@ static DECLARE_WORK(todo_work, key_todo) * * @key: key to add to do item for * @flag: todo flag(s) + * + * Must be called with IRQs or softirqs disabled. */ static void add_todo(struct ieee80211_key *key, u32 flag) { @@ -143,9 +145,9 @@ static void ieee80211_key_enable_hw_acce ret = drv_set_key(key->local, SET_KEY, &sdata->vif, sta, &key->conf); if (!ret) { - spin_lock(&todo_lock); + spin_lock_bh(&todo_lock); key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE; - spin_unlock(&todo_lock); + spin_unlock_bh(&todo_lock); } if (ret && ret != -ENOSPC && ret != -EOPNOTSUPP) @@ -167,12 +169,12 @@ static void ieee80211_key_disable_hw_acc if (!key || !key->local->ops->set_key) return; - spin_lock(&todo_lock); + spin_lock_bh(&todo_lock); if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) { - spin_unlock(&todo_lock); + spin_unlock_bh(&todo_lock); return; } - spin_unlock(&todo_lock); + spin_unlock_bh(&todo_lock); sta = get_sta_for_key(key); sdata = key->sdata; @@ -191,9 +193,9 @@ static void ieee80211_key_disable_hw_acc wiphy_name(key->local->hw.wiphy), key->conf.keyidx, sta ? sta->addr : bcast_addr, ret); - spin_lock(&todo_lock); + spin_lock_bh(&todo_lock); key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; - spin_unlock(&todo_lock); + spin_unlock_bh(&todo_lock); } static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, @@ -440,14 +442,14 @@ void ieee80211_key_link(struct ieee80211 __ieee80211_key_replace(sdata, sta, old_key, key); - spin_unlock_irqrestore(&sdata->local->key_lock, flags); - /* free old key later */ add_todo(old_key, KEY_FLAG_TODO_DELETE); add_todo(key, KEY_FLAG_TODO_ADD_DEBUGFS); if (netif_running(sdata->dev)) add_todo(key, KEY_FLAG_TODO_HWACCEL_ADD); + + spin_unlock_irqrestore(&sdata->local->key_lock, flags); } static void __ieee80211_key_free(struct ieee80211_key *key) @@ -550,7 +552,7 @@ static void __ieee80211_key_todo(void) */ synchronize_rcu(); - spin_lock(&todo_lock); + spin_lock_bh(&todo_lock); while (!list_empty(&todo_list)) { key = list_first_entry(&todo_list, struct ieee80211_key, todo); list_del_init(&key->todo); @@ -561,7 +563,7 @@ static void __ieee80211_key_todo(void) KEY_FLAG_TODO_HWACCEL_REMOVE | KEY_FLAG_TODO_DELETE); key->flags &= ~todoflags; - spin_unlock(&todo_lock); + spin_unlock_bh(&todo_lock); work_done = false; @@ -594,9 +596,9 @@ static void __ieee80211_key_todo(void) WARN_ON(!work_done); - spin_lock(&todo_lock); + spin_lock_bh(&todo_lock); } - spin_unlock(&todo_lock); + spin_unlock_bh(&todo_lock); } void ieee80211_key_todo(void)