From: Johannes Berg Date: Thu, 22 Sep 2016 08:31:41 +0000 (+0200) Subject: iwlwifi: pcie: mark command queue lock with separate lockdep class X-Git-Tag: v4.9-rc6~27^2~73^2~1^2~6 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=faead41cc7213ccef5a58c1bf518ac24816fe8a6;p=linux.git iwlwifi: pcie: mark command queue lock with separate lockdep class Emmanuel reports that when CMD_WANT_ASYNC_CALLBACK is used by mvm, the callback will be called with the command queue lock held, and mvm will try to stop all (other) TX queues, which acquires their locks - this caused a false lockdep recursive locking report. Suppress this report by marking the command queue lock with a new, separate, lock class so lockdep can tell the difference between the two types of queues. Fixes: 156f92f2b471 ("iwlwifi: block the queues when we send ADD_STA for uAPSD") Reported-by: Emmanuel Grumbach Signed-off-by: Johannes Berg Signed-off-by: Luca Coelho --- diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c index e9a278b60dfd..5f840f16f40b 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c @@ -592,6 +592,7 @@ static int iwl_pcie_txq_alloc(struct iwl_trans *trans, static int iwl_pcie_txq_init(struct iwl_trans *trans, struct iwl_txq *txq, int slots_num, u32 txq_id) { + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); int ret; txq->need_update = false; @@ -606,6 +607,13 @@ static int iwl_pcie_txq_init(struct iwl_trans *trans, struct iwl_txq *txq, return ret; spin_lock_init(&txq->lock); + + if (txq_id == trans_pcie->cmd_queue) { + static struct lock_class_key iwl_pcie_cmd_queue_lock_class; + + lockdep_set_class(&txq->lock, &iwl_pcie_cmd_queue_lock_class); + } + __skb_queue_head_init(&txq->overflow_q); /*