[PATCH 3.17 117/122] iwlwifi: mvm: ROC - bug fixes around time events and locking

From: Greg Kroah-Hartman
Date: Fri Dec 05 2014 - 18:37:43 EST


3.17-stable review patch. If anyone has any objections, please let me know.

------------------

From: Matti Gottlieb <matti.gottlieb@xxxxxxxxx>

commit a6cc5163149532734b84c86cbffa4994e527074b upstream.

Don't add the time event to the list. We added it several
times the same time event, which leads to an infinite loop
when walking the list.

Since we (currently) don't support more than one ROC for STA
vif at a time, enforce this and don't add the time event
to any list.

We were also missing the locking of the mutex which led to
a lockdep splat - fix that.

Signed-off-by: Matti Gottlieb <matti.gottlieb@xxxxxxxxx>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/wireless/iwlwifi/mvm/mac80211.c | 25 ++++++++++++++++---------
drivers/net/wireless/iwlwifi/mvm/time-event.c | 2 +-
2 files changed, 17 insertions(+), 10 deletions(-)

--- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
@@ -515,7 +515,8 @@ static void iwl_mvm_mac_tx(struct ieee80
}

if (IEEE80211_SKB_CB(skb)->hw_queue == IWL_MVM_OFFCHANNEL_QUEUE &&
- !test_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status))
+ !test_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status) &&
+ !test_bit(IWL_MVM_STATUS_ROC_AUX_RUNNING, &mvm->status))
goto drop;

/* treat non-bufferable MMPDUs as broadcast if sta is sleeping */
@@ -2403,14 +2404,19 @@ static int iwl_mvm_send_aux_roc_cmd(stru
/* Set the node address */
memcpy(aux_roc_req.node_addr, vif->addr, ETH_ALEN);

+ lockdep_assert_held(&mvm->mutex);
+
+ spin_lock_bh(&mvm->time_event_lock);
+
+ if (WARN_ON(te_data->id == HOT_SPOT_CMD)) {
+ spin_unlock_bh(&mvm->time_event_lock);
+ return -EIO;
+ }
+
te_data->vif = vif;
te_data->duration = duration;
te_data->id = HOT_SPOT_CMD;

- lockdep_assert_held(&mvm->mutex);
-
- spin_lock_bh(&mvm->time_event_lock);
- list_add_tail(&te_data->list, &mvm->time_event_list);
spin_unlock_bh(&mvm->time_event_lock);

/*
@@ -2466,22 +2472,23 @@ static int iwl_mvm_roc(struct ieee80211_
IWL_DEBUG_MAC80211(mvm, "enter (%d, %d, %d)\n", channel->hw_value,
duration, type);

+ mutex_lock(&mvm->mutex);
+
switch (vif->type) {
case NL80211_IFTYPE_STATION:
/* Use aux roc framework (HS20) */
ret = iwl_mvm_send_aux_roc_cmd(mvm, channel,
vif, duration);
- return ret;
+ goto out_unlock;
case NL80211_IFTYPE_P2P_DEVICE:
/* handle below */
break;
default:
IWL_ERR(mvm, "vif isn't P2P_DEVICE: %d\n", vif->type);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out_unlock;
}

- mutex_lock(&mvm->mutex);
-
for (i = 0; i < NUM_PHY_CTX; i++) {
phy_ctxt = &mvm->phy_ctxts[i];
if (phy_ctxt->ref == 0 || mvmvif->phy_ctxt == phy_ctxt)
--- a/drivers/net/wireless/iwlwifi/mvm/time-event.c
+++ b/drivers/net/wireless/iwlwifi/mvm/time-event.c
@@ -303,8 +303,8 @@ static int iwl_mvm_aux_roc_te_handle_not
te_data->running = false;
te_data->vif = NULL;
te_data->uid = 0;
+ te_data->id = TE_MAX;
} else if (le32_to_cpu(notif->action) == TE_V2_NOTIF_HOST_EVENT_START) {
- set_bit(IWL_MVM_STATUS_ROC_RUNNING, &mvm->status);
set_bit(IWL_MVM_STATUS_ROC_AUX_RUNNING, &mvm->status);
te_data->running = true;
ieee80211_ready_on_channel(mvm->hw); /* Start TE */


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