From df8e1af22cee900826112e8e4612cbeb2b168929 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sun, 4 Sep 2022 21:29:10 +0200 Subject: [PATCH] wifi: cw1200: remove RCU STA pointer handling in TX We can call this in one of two ways: through mac80211, where we're already in an RCU read-side critical section, or from some other code in the driver where this pointer can only be NULL. In any case, we get a 'free' already protected pointer to the sta through info->control.sta, so we can use it on the stack without any further protection. Remove the rcu_dereference() and critical section. Signed-off-by: Johannes Berg Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20220904212910.e5bc20dd17bf.Ib570ff7fde33c2b6eddef493a3541fa04eb47181@changeid --- drivers/net/wireless/st/cw1200/txrx.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/net/wireless/st/cw1200/txrx.c b/drivers/net/wireless/st/cw1200/txrx.c index fde21fca6c5e..ab19e0403dc2 100644 --- a/drivers/net/wireless/st/cw1200/txrx.c +++ b/drivers/net/wireless/st/cw1200/txrx.c @@ -762,8 +762,7 @@ void cw1200_tx(struct ieee80211_hw *dev, if (ret) goto drop; - rcu_read_lock(); - sta = rcu_dereference(t.sta); + sta = t.sta; spin_lock_bh(&priv->ps_state_lock); { @@ -776,8 +775,6 @@ void cw1200_tx(struct ieee80211_hw *dev, if (tid_update && sta) ieee80211_sta_set_buffered(sta, t.txpriv.tid, true); - rcu_read_unlock(); - cw1200_bh_wakeup(priv); return;