2012-04-18 15:05:44

by Wey-Yi Guy

[permalink] [raw]
Subject: [PATCH 3.4] iwlwifi: do not nulify ctx->vif on reset

From: Stanislaw Gruszka <[email protected]>

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.

Cc: [email protected]
Signed-off-by: Stanislaw Gruszka <[email protected]>
Signed-off-by: Wey-Yi Guy <[email protected]>
---
this patch will be also available from wireless branch on
git://git.kernel.org/pub/scm/linux/kernel/git/iwlwifi/iwlwifi.git

drivers/net/wireless/iwlwifi/iwl-agn.c | 3 ---
drivers/net/wireless/iwlwifi/iwl-mac80211.c | 10 +++++++++-
2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index f1226db..2a9a16f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -863,7 +863,6 @@ static void iwl_bg_run_time_calib_work(struct work_struct *work)

void iwlagn_prepare_restart(struct iwl_priv *priv)
{
- struct iwl_rxon_context *ctx;
bool bt_full_concurrent;
u8 bt_ci_compliance;
u8 bt_load;
@@ -872,8 +871,6 @@ void iwlagn_prepare_restart(struct iwl_priv *priv)

lockdep_assert_held(&priv->mutex);

- for_each_context(priv, ctx)
- ctx->vif = NULL;
priv->is_open = 0;

/*
diff --git a/drivers/net/wireless/iwlwifi/iwl-mac80211.c b/drivers/net/wireless/iwlwifi/iwl-mac80211.c
index b6805f8..c24a713 100644
--- a/drivers/net/wireless/iwlwifi/iwl-mac80211.c
+++ b/drivers/net/wireless/iwlwifi/iwl-mac80211.c
@@ -1244,6 +1244,7 @@ static 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);
@@ -1265,6 +1266,13 @@ static 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)) {
@@ -1291,7 +1299,7 @@ static 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;
--
1.7.0.4