From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0C98C433ED for ; Wed, 7 Apr 2021 07:55:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6787861130 for ; Wed, 7 Apr 2021 07:55:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234211AbhDGH4C (ORCPT ); Wed, 7 Apr 2021 03:56:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229529AbhDGHz7 (ORCPT ); Wed, 7 Apr 2021 03:55:59 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59953C06174A for ; Wed, 7 Apr 2021 00:55:49 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1lU32M-008Tw9-8V; Wed, 07 Apr 2021 09:55:42 +0200 Message-ID: <95b6c4b34da1173faf226246ea25b47a8fd395b7.camel@sipsolutions.net> Subject: Re: [PATCH] iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_gen2_enqueue_hcmd() From: Johannes Berg To: Jiri Kosina , Heiner Kallweit Cc: Kalle Valo , linux-wireless Date: Wed, 07 Apr 2021 09:55:41 +0200 In-Reply-To: (sfid-20210407_095129_306913_82B5BB2F) References: (sfid-20210407_095129_306913_82B5BB2F) Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-malware-bazaar: not-scanned Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Wed, 2021-04-07 at 09:51 +0200, Jiri Kosina wrote: > On Wed, 7 Apr 2021, Heiner Kallweit wrote: > > > Same fix as in 2800aadc18a6 ("iwlwifi: Fix softirq/hardirq disabling in > > iwl_pcie_enqueue_hcmd()") is needed for iwl_pcie_gen2_enqueue_hcmd. > > I get the same lockdep warning on AX210. > > Makes sense, it's being called from exactly the same contexts. I'm guessing nobody saw this before because the LEDs stuff is not supported/used on newer devices :) Still makes sense though. Btw, I had a fix for your patch for some devices, see below. Already in our tree, so Luca will send it on the way, just FYI/review here. Thanks, johannes From: Johannes Berg Date: Tue, 6 Apr 2021 16:50:23 +0200 Subject: [PATCH] [BUGFIX] iwlwifi: pcie: don't enable BHs with IRQs disabled After the fix from Jiri that disabled local IRQs instead of just BHs (necessary to fix an issue with submitting a command with IRQs already disabled), there was still a situation in which we could deep in there enable BHs, if the device config sets the apmg_wake_up_wa configuration, which is true on all 7000 series devices. To fix that, but not require reverting commit 1ed08f6fb5ae ("iwlwifi: remove flags argument for nic_access"), split up nic access into a version with BH manipulation to use most of the time, and without it for this specific case where the local IRQs are already disabled. Signed-off-by: Johannes Berg --- .../wireless/intel/iwlwifi/pcie/internal.h | 5 ++++ .../net/wireless/intel/iwlwifi/pcie/trans.c | 24 ++++++++++++++++--- drivers/net/wireless/intel/iwlwifi/pcie/tx.c | 4 ++-- 3 files changed, 28 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h index 2c2389feb5e1..0b99f0c34111 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h @@ -453,6 +453,11 @@ struct iwl_trans const struct iwl_cfg_trans_params *cfg_trans); void iwl_trans_pcie_free(struct iwl_trans *trans); +bool __iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans); +#define _iwl_trans_pcie_grab_nic_access(trans) \ + __cond_lock(nic_access_nobh, \ + likely(__iwl_trans_pcie_grab_nic_access(trans))) + /***************************************************** * RX ******************************************************/ diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index f2869fc343e3..bf36fa72f22e 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -2047,12 +2047,16 @@ static void iwl_trans_pcie_removal_wk(struct work_struct *wk) module_put(THIS_MODULE); } -static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans) +/* + * This version doesn't disable BHs but rather assumes they're + * already disabled. + */ +bool __iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans) { int ret; struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); - spin_lock_bh(&trans_pcie->reg_lock); + spin_lock(&trans_pcie->reg_lock); if (trans_pcie->cmd_hold_nic_awake) goto out; @@ -2137,7 +2141,7 @@ static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans) } err: - spin_unlock_bh(&trans_pcie->reg_lock); + spin_unlock(&trans_pcie->reg_lock); return false; } @@ -2150,6 +2154,20 @@ out: return true; } +static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans) +{ + bool ret; + + local_bh_disable(); + ret = __iwl_trans_pcie_grab_nic_access(trans); + if (ret) { + /* keep BHs disabled until iwl_trans_pcie_release_nic_access */ + return ret; + } + local_bh_enable(); + return false; +} + static void iwl_trans_pcie_release_nic_access(struct iwl_trans *trans) { struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c index 0346505351f5..4f6c187eed69 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c @@ -643,7 +643,7 @@ static int iwl_pcie_set_cmd_in_flight(struct iwl_trans *trans, * returned. This needs to be done only on NICs that have * apmg_wake_up_wa set (see above.) */ - if (!iwl_trans_grab_nic_access(trans)) + if (!_iwl_trans_pcie_grab_nic_access(trans)) return -EIO; /* @@ -652,7 +652,7 @@ static int iwl_pcie_set_cmd_in_flight(struct iwl_trans *trans, * already true, so it's OK to unconditionally set it to true. */ trans_pcie->cmd_hold_nic_awake = true; - spin_unlock_bh(&trans_pcie->reg_lock); + spin_unlock(&trans_pcie->reg_lock); return 0; } -- 2.30.2