[PATCH 4/6] wifi: mt76: mt7915: fix list corruption after hardware restart

[Felix Fietkau <nbd@nbd.name>]

Since stations are recreated from scratch, all lists that wcids are added
to must be cleared before calling ieee80211_restart_hw.
Set wcid->sta = 0 for each wcid entry in order to ensure that they are
not added again before they are ready.

Fixes: 8a55712d124f ("wifi: mt76: mt7915: enable full system reset support")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 drivers/net/wireless/mediatek/mt76/mac80211.c | 37 +++++++++++++++++++
 drivers/net/wireless/mediatek/mt76/mt76.h     |  1 +
 .../net/wireless/mediatek/mt76/mt7915/mac.c   | 12 +++---
 3 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c
index 6b2641a9ae9a..0e0d7b3bfe42 100644
--- a/drivers/net/wireless/mediatek/mt76/mac80211.c
+++ b/drivers/net/wireless/mediatek/mt76/mac80211.c
@@ -818,6 +818,43 @@ void mt76_free_device(struct mt76_dev *dev)
 }
 EXPORT_SYMBOL_GPL(mt76_free_device);
 
+static void mt76_reset_phy(struct mt76_phy *phy)
+{
+	if (!phy)
+		return;
+
+	INIT_LIST_HEAD(&phy->tx_list);
+}
+
+void mt76_reset_device(struct mt76_dev *dev)
+{
+	int i;
+
+	rcu_read_lock();
+	for (i = 0; i < ARRAY_SIZE(dev->wcid); i++) {
+		struct mt76_wcid *wcid;
+
+		wcid = rcu_dereference(dev->wcid[i]);
+		if (!wcid)
+			continue;
+
+		wcid->sta = 0;
+		mt76_wcid_cleanup(dev, wcid);
+		rcu_assign_pointer(dev->wcid[i], NULL);
+	}
+	rcu_read_unlock();
+
+	INIT_LIST_HEAD(&dev->wcid_list);
+	INIT_LIST_HEAD(&dev->sta_poll_list);
+	dev->vif_mask = 0;
+	memset(dev->wcid_mask, 0, sizeof(dev->wcid_mask));
+
+	mt76_reset_phy(&dev->phy);
+	for (i = 0; i < ARRAY_SIZE(dev->phys); i++)
+		mt76_reset_phy(dev->phys[i]);
+}
+EXPORT_SYMBOL_GPL(mt76_reset_device);
+
 struct mt76_phy *mt76_vif_phy(struct ieee80211_hw *hw,
 			      struct ieee80211_vif *vif)
 {
diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index febe1dcb8d19..5c71226c8607 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -1247,6 +1247,7 @@ int mt76_register_device(struct mt76_dev *dev, bool vht,
 			 struct ieee80211_rate *rates, int n_rates);
 void mt76_unregister_device(struct mt76_dev *dev);
 void mt76_free_device(struct mt76_dev *dev);
+void mt76_reset_device(struct mt76_dev *dev);
 void mt76_unregister_phy(struct mt76_phy *phy);
 
 struct mt76_phy *mt76_alloc_radio_phy(struct mt76_dev *dev, unsigned int size,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
index 09c92e4ae129..5da7bb90e209 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
@@ -1460,17 +1460,15 @@ mt7915_mac_full_reset(struct mt7915_dev *dev)
 	if (i == 10)
 		dev_err(dev->mt76.dev, "chip full reset failed\n");
 
-	spin_lock_bh(&dev->mt76.sta_poll_lock);
-	while (!list_empty(&dev->mt76.sta_poll_list))
-		list_del_init(dev->mt76.sta_poll_list.next);
-	spin_unlock_bh(&dev->mt76.sta_poll_lock);
-
-	memset(dev->mt76.wcid_mask, 0, sizeof(dev->mt76.wcid_mask));
-	dev->mt76.vif_mask = 0;
 	dev->phy.omac_mask = 0;
 	if (phy2)
 		phy2->omac_mask = 0;
 
+	mt76_reset_device(&dev->mt76);
+
+	INIT_LIST_HEAD(&dev->sta_rc_list);
+	INIT_LIST_HEAD(&dev->twt_list);
+
 	i = mt76_wcid_alloc(dev->mt76.wcid_mask, MT7915_WTBL_STA);
 	dev->mt76.global_wcid.idx = i;
 	dev->recovery.hw_full_reset = false;
-- 
2.51.0