| Message ID | 0686097db95ae32ce6805e5163798d912b394f37.1613171185.git.skhan@linuxfoundation.org (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | Add lockdep_assert_not_held() | expand |
Shuah Khan <skhan@linuxfoundation.org> writes: > 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/linux-wireless/871rdmu9z9.fsf@codeaurora.org/ > Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> This can go via the same tree as patch 1: Acked-by: Kalle Valo <kvalo@codeaurora.org> But I can also take this to my ath tree, once patch 1 has reached it. Just let me know what is preferred.
diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c index c202b167d8c6..7de05b679ad2 100644 --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -4728,6 +4728,8 @@ 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();
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/linux-wireless/871rdmu9z9.fsf@codeaurora.org/ Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> --- drivers/net/wireless/ath/ath10k/mac.c | 2 ++ 1 file changed, 2 insertions(+)