diff mbox series

[1/2] wifi: iwlwifi: mvm: fix mvmtxq->stopped handling

Message ID 20230317105323.3893cb26df9d.I68fc8d1a16a7c6927ac92fe855ada741acb9fe14@changeid
State New
Headers show
Series [1/2] wifi: iwlwifi: mvm: fix mvmtxq->stopped handling | expand

Commit Message

Johannes Berg March 17, 2023, 9:53 a.m. UTC
From: Johannes Berg <johannes.berg@intel.com>

This could race if the queue is redirected while full, then
the flushing internally would start it while it's not yet
usable again. Fix it by using two state bits instead of just
one.

Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Tested-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c | 5 ++++-
 drivers/net/wireless/intel/iwlwifi/mvm/mvm.h      | 4 +++-
 drivers/net/wireless/intel/iwlwifi/mvm/ops.c      | 5 ++++-
 drivers/net/wireless/intel/iwlwifi/mvm/sta.c      | 4 ++--
 4 files changed, 13 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index 74ded790d5a4..af6d5c55c31e 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -782,7 +782,10 @@  void iwl_mvm_mac_itxq_xmit(struct ieee80211_hw *hw, struct ieee80211_txq *txq)
 
 	rcu_read_lock();
 	do {
-		while (likely(!mvmtxq->stopped &&
+		while (likely(!test_bit(IWL_MVM_TXQ_STATE_STOP_FULL,
+					&mvmtxq->state) &&
+			      !test_bit(IWL_MVM_TXQ_STATE_STOP_REDIRECT,
+					&mvmtxq->state) &&
 			      !test_bit(IWL_MVM_STATUS_IN_D3, &mvm->status))) {
 			skb = ieee80211_tx_dequeue(hw, txq);
 
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
index d431145929be..569cf13bb03a 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
@@ -732,7 +732,9 @@  struct iwl_mvm_txq {
 	struct list_head list;
 	u16 txq_id;
 	atomic_t tx_request;
-	bool stopped;
+#define IWL_MVM_TXQ_STATE_STOP_FULL	0
+#define IWL_MVM_TXQ_STATE_STOP_REDIRECT	1
+	unsigned long state;
 };
 
 static inline struct iwl_mvm_txq *
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
index 70926bb1df6c..467da97bd2fa 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
@@ -1713,7 +1713,10 @@  static void iwl_mvm_queue_state_change(struct iwl_op_mode *op_mode,
 
 		txq = sta->txq[tid];
 		mvmtxq = iwl_mvm_txq_from_mac80211(txq);
-		mvmtxq->stopped = !start;
+		if (start)
+			clear_bit(IWL_MVM_TXQ_STATE_STOP_FULL, &mvmtxq->state);
+		else
+			set_bit(IWL_MVM_TXQ_STATE_STOP_FULL, &mvmtxq->state);
 
 		if (start && mvmsta->sta_state != IEEE80211_STA_NOTEXIST)
 			iwl_mvm_mac_itxq_xmit(mvm->hw, txq);
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index e976c3cada1b..0f5697f0df50 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -710,7 +710,7 @@  static int iwl_mvm_redirect_queue(struct iwl_mvm *mvm, int queue, int tid,
 			    queue, iwl_mvm_ac_to_tx_fifo[ac]);
 
 	/* Stop the queue and wait for it to empty */
-	txq->stopped = true;
+	set_bit(IWL_MVM_TXQ_STATE_STOP_REDIRECT, &txq->state);
 
 	ret = iwl_trans_wait_tx_queues_empty(mvm->trans, BIT(queue));
 	if (ret) {
@@ -753,7 +753,7 @@  static int iwl_mvm_redirect_queue(struct iwl_mvm *mvm, int queue, int tid,
 
 out:
 	/* Continue using the queue */
-	txq->stopped = false;
+	clear_bit(IWL_MVM_TXQ_STATE_STOP_REDIRECT, &txq->state);
 
 	return ret;
 }