Return-path: Received: from mtiwmhc12.worldnet.att.net ([204.127.131.116]:60747 "EHLO mtiwmhc12.worldnet.att.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752069AbYG3GMi (ORCPT ); Wed, 30 Jul 2008 02:12:38 -0400 Message-ID: <48900654.7030100@lwfinger.net> (sfid-20080730_081252_829123_A992B211) Date: Wed, 30 Jul 2008 01:12:36 -0500 From: Larry Finger MIME-Version: 1.0 To: Hin-Tak Leung , herton Ronaldo Krzesinski , Pavel Roskin CC: wireless Subject: [RFC/RFT] rtl8187: Protect the config callback from mac80211 with a mutex Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: Herton, Does this patch help your problem? I haven't done much testing, but things seem to be better with it here. Larry ================== Some users of the RTL8187B have experienced difficulties since commit 8f87dd7e540d455f8e7f11478133b85edc969c67 that introduced the power management wext hooks. This difficulty has not made much sense until it was realized that it was possible for mac80211 to make a call to the config routine while that routine was already being executed. This patch protects the critical section with a mutex. Signed-off-by: Larry Finger --- Index: wireless-testing/drivers/net/wireless/rtl8187.h =================================================================== --- wireless-testing.orig/drivers/net/wireless/rtl8187.h +++ wireless-testing/drivers/net/wireless/rtl8187.h @@ -94,6 +94,7 @@ struct rtl8187_priv { const struct rtl818x_rf_ops *rf; struct ieee80211_vif *vif; int mode; + struct mutex mutex; /* used to lock config callback */ /* rtl8187 specific */ struct ieee80211_channel channels[14]; Index: wireless-testing/drivers/net/wireless/rtl8187_dev.c =================================================================== --- wireless-testing.orig/drivers/net/wireless/rtl8187_dev.c +++ wireless-testing/drivers/net/wireless/rtl8187_dev.c @@ -864,6 +864,7 @@ static int rtl8187_config(struct ieee802 struct rtl8187_priv *priv = dev->priv; u32 reg; + mutex_lock(&priv->mutex); reg = rtl818x_ioread32(priv, &priv->map->TX_CONF); /* Enable TX loopback on MAC level to avoid TX during channel * changes, as this has be seen to causes problems and the @@ -896,6 +897,7 @@ static int rtl8187_config(struct ieee802 rtl818x_iowrite16(priv, &priv->map->ATIMTR_INTERVAL, 100); rtl818x_iowrite16(priv, &priv->map->BEACON_INTERVAL, 100); rtl818x_iowrite16(priv, &priv->map->BEACON_INTERVAL_TIME, 100); + mutex_unlock(&priv->mutex); return 0; } @@ -1187,6 +1189,7 @@ static int __devinit rtl8187_probe(struc printk(KERN_ERR "rtl8187: Cannot register device\n"); goto err_free_dev; } + mutex_init(&priv->mutex); printk(KERN_INFO "%s: hwaddr %s, %s V%d + %s\n", wiphy_name(dev->wiphy), print_mac(mac, dev->wiphy->perm_addr),