Messages in this thread Patch in this message | | | Date | Sat, 06 Mar 2021 11:54:34 -0000 | From | "tip-bot2 for Shuah Khan" <> | Subject | [tip: locking/core] ath10k: Detect conf_mutex held ath10k_drain_tx() calls |
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The following commit has been merged into the locking/core branch of tip:
Commit-ID: bdb1050ee1faaec1e78c15de8b1959176f26c655 Gitweb: https://git.kernel.org/tip/bdb1050ee1faaec1e78c15de8b1959176f26c655 Author: Shuah Khan <skhan@linuxfoundation.org> AuthorDate: Fri, 26 Feb 2021 17:07:00 -07:00 Committer: Ingo Molnar <mingo@kernel.org> CommitterDate: Sat, 06 Mar 2021 12:51:15 +01:00
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 <skhan@linuxfoundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/linux-wireless/871rdmu9z9.fsf@codeaurora.org/ --- 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 bb6c5ee..5ce4f8d 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();
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