From bdb1050ee1faaec1e78c15de8b1959176f26c655 Mon Sep 17 00:00:00 2001 From: Shuah Khan Date: Fri, 26 Feb 2021 17:07:00 -0700 Subject: ath10k: Detect conf_mutex held ath10k_drain_tx() calls 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. Signed-off-by: Shuah Khan Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Acked-by: Kalle Valo Link: https://lore.kernel.org/linux-wireless/871rdmu9z9.fsf@codeaurora.org/ --- drivers/net/wireless/ath/ath10k/mac.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers') diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c index bb6c5ee43ac0..5ce4f8d038b9 100644 --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -4727,6 +4727,8 @@ out: /* 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(); -- cgit v1.2.3