ath10k_drain_tx() must not be called with conf_mutex held as workers can use that also. Add call to lockdep_assert_not_held() on conf_mutex to detect if conf_mutex is held by the caller. The idea for this patch stemmed from coming across the comment block above the ath10k_drain_tx() while reviewing the conf_mutex holds during to debug the conf_mutex lock assert in ath10k_debug_fw_stats_request(). Adding detection to assert on conf_mutex hold will help detect incorrect usages that could lead to locking problems when async worker routines try to call this routine. Link: https://lore.kernel.org/lkml/37a29c383bff2fb1605241ee6c7c9be3784fb3c6.1613171185.git.skhan@xxxxxxxxxxxxxxxxxxx/ Link: https://lore.kernel.org/linux-wireless/871rdmu9z9.fsf@xxxxxxxxxxxxxx/ Acked-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/ath10k/mac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c index 7d98250380ec..a595ff4f0843 100644 --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -4567,6 +4567,8 @@ static void ath10k_mac_op_wake_tx_queue(struct ieee80211_hw *hw, /* Must not be called with conf_mutex held as workers can use that also. */ void ath10k_drain_tx(struct ath10k *ar) { + lockdep_assert_not_held(&ar->conf_mutex); + /* make sure rcu-protected mac80211 tx path itself is drained */ synchronize_net(); -- 2.27.0
