From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58096 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966552AbcKXP33 (ORCPT ); Thu, 24 Nov 2016 10:29:29 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Emmanuel Grumbach , Johannes Berg , Luca Coelho Subject: [PATCH 4.8 40/67] iwlwifi: pcie: mark command queue lock with separate lockdep class Date: Thu, 24 Nov 2016 16:27:34 +0100 Message-Id: <20161124145459.569151912@linuxfoundation.org> In-Reply-To: <20161124145457.061710350@linuxfoundation.org> References: <20161124145457.061710350@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg commit faead41cc7213ccef5a58c1bf518ac24816fe8a6 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/intel/iwlwifi/pcie/tx.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c @@ -522,6 +522,7 @@ error: 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; @@ -536,6 +537,13 @@ static int iwl_pcie_txq_init(struct iwl_ 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); /*