iwlwifi: do not nulify ctx->vif on reset

commit 8db4c7e25d153fb049e81715d72fa3be3a0c3b69 upstream.

ctx->vif is dereferenced in different part of iwlwifi code, so do not
nullify it.

This should address at least one of the possible reasons of WARNING at
iwlagn_mac_remove_interface, and perhaps some random crashes when
firmware reset is performed.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2:
 - Change filename iwl-mac80211.c to iwl-core.c
 - Change context in iwlagn_prepare_restart()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index e0e9a3dfbc00a2febd8ce146bc8c3d02bc8e312a..d7d2512241fde5fb371a1516c0f03ffe2a8767bf 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -1504,7 +1504,6 @@ static void iwl_bg_run_time_calib_work(struct work_struct *work)
 
 static void iwlagn_prepare_restart(struct iwl_priv *priv)
 {
-       struct iwl_rxon_context *ctx;
        bool bt_full_concurrent;
        u8 bt_ci_compliance;
        u8 bt_load;
@@ -1513,8 +1512,6 @@ static void iwlagn_prepare_restart(struct iwl_priv *priv)
 
        lockdep_assert_held(&priv->shrd->mutex);
 
-       for_each_context(priv, ctx)
-               ctx->vif = NULL;
        priv->is_open = 0;
 
        /*

diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 3d75d4c45e250a86fc967d746f139037638a1768..832ec4d9989e08725f9f0d383fb2ac5b311412ff 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -1228,6 +1228,7 @@ int iwlagn_mac_add_interface(struct ieee80211_hw *hw,
        struct iwl_rxon_context *tmp, *ctx = NULL;
        int err;
        enum nl80211_iftype viftype = ieee80211_vif_type_p2p(vif);
+       bool reset = false;
 
        IWL_DEBUG_MAC80211(priv, "enter: type %d, addr %pM\n",
                           viftype, vif->addr);
@@ -1249,6 +1250,13 @@ int iwlagn_mac_add_interface(struct ieee80211_hw *hw,
                        tmp->interface_modes | tmp->exclusive_interface_modes;
 
                if (tmp->vif) {
+                       /* On reset we need to add the same interface again */
+                       if (tmp->vif == vif) {
+                               reset = true;
+                               ctx = tmp;
+                               break;
+                       }
+
                        /* check if this busy context is exclusive */
                        if (tmp->exclusive_interface_modes &
                                                BIT(tmp->vif->type)) {
@@ -1275,7 +1283,7 @@ int iwlagn_mac_add_interface(struct ieee80211_hw *hw,
        ctx->vif = vif;
 
        err = iwl_setup_interface(priv, ctx);
-       if (!err)
+       if (!err || reset)
                goto out;
 
        ctx->vif = NULL;