From patchwork Tue Apr 23 10:37:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanislaw Gruszka X-Patchwork-Id: 10912717 X-Patchwork-Delegate: nbd@nbd.name Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EB3C51515 for ; Tue, 23 Apr 2019 10:37:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DDE26286B5 for ; Tue, 23 Apr 2019 10:37:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D282828806; Tue, 23 Apr 2019 10:37:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5DA7F286B5 for ; Tue, 23 Apr 2019 10:37:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727307AbfDWKhW (ORCPT ); Tue, 23 Apr 2019 06:37:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40050 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726033AbfDWKhW (ORCPT ); Tue, 23 Apr 2019 06:37:22 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0B82930ADBC0; Tue, 23 Apr 2019 10:37:22 +0000 (UTC) Received: from localhost (ovpn-204-59.brq.redhat.com [10.40.204.59]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6F2996013D; Tue, 23 Apr 2019 10:37:19 +0000 (UTC) From: Stanislaw Gruszka To: linux-wireless@vger.kernel.org Cc: Felix Fietkau , Lorenzo Bianconi Subject: [PATCH v2 3/3] mt76x02: remove bogus mutex usage Date: Tue, 23 Apr 2019 12:37:09 +0200 Message-Id: <20190423103709.7272-4-sgruszka@redhat.com> In-Reply-To: <20190423103709.7272-1-sgruszka@redhat.com> References: <20190423103709.7272-1-sgruszka@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Tue, 23 Apr 2019 10:37:22 +0000 (UTC) Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP mac80211 .start(), .stop() callbacks are never called concurrently with other callbacks. The only concurencly is with mt76 works which we cancel on stop() and schedule on start(). This fixes possible deadlock on cancel_delayed_work_sync(&dev->mac_work) as mac_work also take mutex. Signed-off-by: Stanislaw Gruszka --- .../net/wireless/mediatek/mt76/mt76x0/pci.c | 6 ----- .../net/wireless/mediatek/mt76/mt76x0/usb.c | 22 +++++-------------- .../wireless/mediatek/mt76/mt76x2/pci_main.c | 13 +++-------- .../wireless/mediatek/mt76/mt76x2/usb_main.c | 10 ++------- 4 files changed, 10 insertions(+), 41 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt76x0/pci.c b/drivers/net/wireless/mediatek/mt76/mt76x0/pci.c index 156d3d064ba0..ac979128386a 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x0/pci.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x0/pci.c @@ -25,8 +25,6 @@ static int mt76x0e_start(struct ieee80211_hw *hw) { struct mt76x02_dev *dev = hw->priv; - mutex_lock(&dev->mt76.mutex); - mt76x02_mac_start(dev); mt76x0_phy_calibrate(dev, true); ieee80211_queue_delayed_work(dev->mt76.hw, &dev->mac_work, @@ -35,8 +33,6 @@ static int mt76x0e_start(struct ieee80211_hw *hw) MT_CALIBRATE_INTERVAL); set_bit(MT76_STATE_RUNNING, &dev->mt76.state); - mutex_unlock(&dev->mt76.mutex); - return 0; } @@ -62,10 +58,8 @@ static void mt76x0e_stop(struct ieee80211_hw *hw) { struct mt76x02_dev *dev = hw->priv; - mutex_lock(&dev->mt76.mutex); clear_bit(MT76_STATE_RUNNING, &dev->mt76.state); mt76x0e_stop_hw(dev); - mutex_unlock(&dev->mt76.mutex); } static void diff --git a/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c b/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c index 22c10722019d..494b9f35f80d 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x0/usb.c @@ -81,8 +81,10 @@ static void mt76x0u_cleanup(struct mt76x02_dev *dev) mt76u_queues_deinit(&dev->mt76); } -static void mt76x0u_mac_stop(struct mt76x02_dev *dev) +static void mt76x0u_stop(struct ieee80211_hw *hw) { + struct mt76x02_dev *dev = hw->priv; + clear_bit(MT76_STATE_RUNNING, &dev->mt76.state); cancel_delayed_work_sync(&dev->cal_work); cancel_delayed_work_sync(&dev->mac_work); @@ -106,11 +108,9 @@ static int mt76x0u_start(struct ieee80211_hw *hw) struct mt76x02_dev *dev = hw->priv; int ret; - mutex_lock(&dev->mt76.mutex); - ret = mt76x0_mac_start(dev); if (ret) - goto out; + return ret; mt76x0_phy_calibrate(dev, true); ieee80211_queue_delayed_work(dev->mt76.hw, &dev->mac_work, @@ -118,19 +118,7 @@ static int mt76x0u_start(struct ieee80211_hw *hw) ieee80211_queue_delayed_work(dev->mt76.hw, &dev->cal_work, MT_CALIBRATE_INTERVAL); set_bit(MT76_STATE_RUNNING, &dev->mt76.state); - -out: - mutex_unlock(&dev->mt76.mutex); - return ret; -} - -static void mt76x0u_stop(struct ieee80211_hw *hw) -{ - struct mt76x02_dev *dev = hw->priv; - - mutex_lock(&dev->mt76.mutex); - mt76x0u_mac_stop(dev); - mutex_unlock(&dev->mt76.mutex); + return 0; } static const struct ieee80211_ops mt76x0u_ops = { diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2/pci_main.c b/drivers/net/wireless/mediatek/mt76/mt76x2/pci_main.c index 16dc8e2451b5..3947e8ba486e 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2/pci_main.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2/pci_main.c @@ -22,15 +22,13 @@ mt76x2_start(struct ieee80211_hw *hw) struct mt76x02_dev *dev = hw->priv; int ret; - mutex_lock(&dev->mt76.mutex); - ret = mt76x2_mac_start(dev); if (ret) - goto out; + return ret; ret = mt76x2_phy_start(dev); if (ret) - goto out; + return ret; ieee80211_queue_delayed_work(mt76_hw(dev), &dev->mac_work, MT_MAC_WORK_INTERVAL); @@ -38,10 +36,7 @@ mt76x2_start(struct ieee80211_hw *hw) MT_WATCHDOG_TIME); set_bit(MT76_STATE_RUNNING, &dev->mt76.state); - -out: - mutex_unlock(&dev->mt76.mutex); - return ret; + return 0; } static void @@ -49,10 +44,8 @@ mt76x2_stop(struct ieee80211_hw *hw) { struct mt76x02_dev *dev = hw->priv; - mutex_lock(&dev->mt76.mutex); clear_bit(MT76_STATE_RUNNING, &dev->mt76.state); mt76x2_stop_hardware(dev); - mutex_unlock(&dev->mt76.mutex); } static int diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c b/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c index 0771de210c6a..32726b4906ea 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2/usb_main.c @@ -21,30 +21,24 @@ static int mt76x2u_start(struct ieee80211_hw *hw) struct mt76x02_dev *dev = hw->priv; int ret; - mutex_lock(&dev->mt76.mutex); - ret = mt76x2u_mac_start(dev); if (ret) - goto out; + return ret; ieee80211_queue_delayed_work(mt76_hw(dev), &dev->mac_work, MT_MAC_WORK_INTERVAL); set_bit(MT76_STATE_RUNNING, &dev->mt76.state); -out: - mutex_unlock(&dev->mt76.mutex); - return ret; + return 0; } static void mt76x2u_stop(struct ieee80211_hw *hw) { struct mt76x02_dev *dev = hw->priv; - mutex_lock(&dev->mt76.mutex); clear_bit(MT76_STATE_RUNNING, &dev->mt76.state); mt76u_stop_tx(&dev->mt76); mt76x2u_stop_hw(dev); - mutex_unlock(&dev->mt76.mutex); } static int