[PATCH v2 3/5] ath10k: drain tx before restarting hw

[Michal Kazior]

On 23 May 2014 10:27, Kalle Valo <kvalo at qca.qualcomm.com> wrote:
> Michal Kazior <michal.kazior at tieto.com> writes:
>
>> This makes sure no further tx requests are
>> submitted to HTT before driver teardown.
>>
>> This should prevent invalid pointer/NULL
>> dereference on htt tx pool in ath10k_htt_tx() in
>> some cases of heavy traffic.
>>
>> Reported-By: Ben Greear <greearb at candelatech.com>
>> Signed-off-by: Michal Kazior <michal.kazior at tieto.com>
>
> [...]
>
>> --- a/drivers/net/wireless/ath/ath10k/mac.c
>> +++ b/drivers/net/wireless/ath/ath10k/mac.c
>> @@ -2289,6 +2289,21 @@ static void ath10k_tx(struct ieee80211_hw *hw,
>>  /*
>>   * Initialize various parameters with default vaules.
>>   */
>> +static void ath10k_drain_tx(struct ath10k *ar)
>> +{
>> +     /* workers can hold conf_mutex -- avoid deadlock */
>> +     WARN_ON(lockdep_is_held(&ar->conf_mutex));
>
> If CONFIG_LOCKDEP is disabled this will fail with:
>
> drivers/net/wireless/ath/ath10k/mac.c:2301:2: error: implicit declaration of function 'lockdep_is_held' [-Werror=implicit-function-declaration]
>
> I wasn't able to come up with any other way than adding '#ifdef
> CONFIG_LOCKDEP' which is quite ugly. What should we do?

I guess we could define lockdep_assert_not_held() in debug.h?


Michał