ipw2x00: fix rtnl mutex deadlock

This fix regression introduced by:

commit: ecb4433550f0620f3d1471ae7099037ede30a91e
Author: Stanislaw Gruszka <sgruszka@redhat.com>
Date:   Fri Aug 12 14:00:59 2011 +0200

    mac80211: fix suspend/resume races with unregister hw

Above commit add rtnl_lock() into wiphy_register(), what cause deadlock
when initializing ipw2x00 driver, which itself call wiphy_register()
from register_netdev() internal callback with rtnl mutex taken.

To fix move wiphy_register() outside register_netdev(). This solution
have side effect of not creating /sys/class/net/wlanX/phy80211 link,
but that's a minor issue we can live with.

Bisected-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Bisected-by: Michael Witten <mfwitten@gmail.com>
Tested-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Tested-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 40 insertions, 20 deletions

diff --git a/drivers/net/wireless/ipw2x00/ipw2100.c b/drivers/net/wireless/ipw2x00/ipw2100.c
index 3774dd034746..ef9ad79d1bfd 100644
--- a/drivers/net/wireless/ipw2x00/ipw2100.c
+++ b/drivers/net/wireless/ipw2x00/ipw2100.c
@@ -1903,15 +1903,17 @@ static void ipw2100_down(struct ipw2100_priv *priv)
 static int ipw2100_net_init(struct net_device *dev)
 {
         struct ipw2100_priv *priv = libipw_priv(dev);
+
+        return ipw2100_up(priv, 1);
+}
+
+static int ipw2100_wdev_init(struct net_device *dev)
+{
+        struct ipw2100_priv *priv = libipw_priv(dev);
         const struct libipw_geo *geo = libipw_get_geo(priv->ieee);
         struct wireless_dev *wdev = &priv->ieee->wdev;
-        int ret;
         int i;
 
-        ret = ipw2100_up(priv, 1);
-        if (ret)
-                return ret;
-
         memcpy(wdev->wiphy->perm_addr, priv->mac_addr, ETH_ALEN);
 
         /* fill-out priv->ieee->bg_band */
@@ -6350,9 +6352,13 @@ static int ipw2100_pci_init_one(struct pci_dev *pci_dev,
                        "Error calling register_netdev.\n");
                 goto fail;
         }
+        registered = 1;
+
+        err = ipw2100_wdev_init(dev);
+        if (err)
+                goto fail;
 
         mutex_lock(&priv->action_mutex);
-        registered = 1;
 
         IPW_DEBUG_INFO("%s: Bound to %s\n", dev->name, pci_name(pci_dev));
 
@@ -6389,7 +6395,8 @@ static int ipw2100_pci_init_one(struct pci_dev *pci_dev,
 
       fail_unlock:
         mutex_unlock(&priv->action_mutex);
-
+        wiphy_unregister(priv->ieee->wdev.wiphy);
+        kfree(priv->ieee->bg_band.channels);
       fail:
         if (dev) {
                 if (registered)
diff --git a/drivers/net/wireless/ipw2x00/ipw2200.c b/drivers/net/wireless/ipw2x00/ipw2200.c
index 87813c33bdc2..4ffebede5e03 100644
--- a/drivers/net/wireless/ipw2x00/ipw2200.c
+++ b/drivers/net/wireless/ipw2x00/ipw2200.c
@@ -11425,16 +11425,23 @@ static void ipw_bg_down(struct work_struct *work)
 /* Called by register_netdev() */
 static int ipw_net_init(struct net_device *dev)
 {
+        int rc = 0;
+        struct ipw_priv *priv = libipw_priv(dev);
+
+        mutex_lock(&priv->mutex);
+        if (ipw_up(priv))
+                rc = -EIO;
+        mutex_unlock(&priv->mutex);
+
+        return rc;
+}
+
+static int ipw_wdev_init(struct net_device *dev)
+{
         int i, rc = 0;
         struct ipw_priv *priv = libipw_priv(dev);
         const struct libipw_geo *geo = libipw_get_geo(priv->ieee);
         struct wireless_dev *wdev = &priv->ieee->wdev;
-        mutex_lock(&priv->mutex);
-
-        if (ipw_up(priv)) {
-                rc = -EIO;
-                goto out;
-        }
 
         memcpy(wdev->wiphy->perm_addr, priv->mac_addr, ETH_ALEN);
 
@@ -11519,13 +11526,9 @@ static int ipw_net_init(struct net_device *dev)
         set_wiphy_dev(wdev->wiphy, &priv->pci_dev->dev);
 
         /* With that information in place, we can now register the wiphy... */
-        if (wiphy_register(wdev->wiphy)) {
+        if (wiphy_register(wdev->wiphy))
                 rc = -EIO;
-                goto out;
-        }
-
 out:
-        mutex_unlock(&priv->mutex);
         return rc;
 }
 
@@ -11832,14 +11835,22 @@ static int __devinit ipw_pci_probe(struct pci_dev *pdev,
                 goto out_remove_sysfs;
         }
 
+        err = ipw_wdev_init(net_dev);
+        if (err) {
+                IPW_ERROR("failed to register wireless device\n");
+                goto out_unregister_netdev;
+        }
+
 #ifdef CONFIG_IPW2200_PROMISCUOUS
         if (rtap_iface) {
                 err = ipw_prom_alloc(priv);
                 if (err) {
                         IPW_ERROR("Failed to register promiscuous network "
                                   "device (error %d).\n", err);
-                        unregister_netdev(priv->net_dev);
-                        goto out_remove_sysfs;
+                        wiphy_unregister(priv->ieee->wdev.wiphy);
+                        kfree(priv->ieee->a_band.channels);
+                        kfree(priv->ieee->bg_band.channels);
+                        goto out_unregister_netdev;
                 }
         }
 #endif
@@ -11851,6 +11862,8 @@ static int __devinit ipw_pci_probe(struct pci_dev *pdev,
 
         return 0;
 
+      out_unregister_netdev:
+        unregister_netdev(priv->net_dev);
       out_remove_sysfs:
         sysfs_remove_group(&pdev->dev.kobj, &ipw_attribute_group);
       out_release_irq: