Re: [PATCH] drivers: net: wireless: ath: ath9k: dfs: remove VLA usage

From: Rosen Penev
Date: Fri Mar 09 2018 - 10:42:10 EST


On Fri, Mar 9, 2018 at 5:29 AM, Joe Perches <joe@xxxxxxxxxxx> wrote:
> On Fri, 2018-03-09 at 15:23 +0200, Andreas Christoforou wrote:
>> The kernel would like to have all stack VLA usage removed.
>> This is the correct patch.
> []
>> diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c
> []
>> @@ -101,7 +101,7 @@ static bool ath9k_check_chirping(struct ath_softc *sc, u8 *data,
>> int datalen, bool is_ctl, bool is_ext)
>> {
>> int i;
>> - int max_bin[FFT_NUM_SAMPLES];
>> + int max_bin[NUM_DIFFS + 1];
>> struct ath_hw *ah = sc->sc_ah;
>> struct ath_common *common = ath9k_hw_common(ah);
>> int prev_delta;
>
> why not just change FFT_NUM_SAMPLES to a #define
> or get rid if FFT_NUM_SAMPLES altogether?
>
I did the former yesterday. Never submitted.
> $ git grep -w FFT_NUM_SAMPLES
> drivers/net/wireless/ath/ath9k/dfs.c:static const int FFT_NUM_SAMPLES = (NUM_DIFFS + 1);
> drivers/net/wireless/ath/ath9k/dfs.c: int max_bin[FFT_NUM_SAMPLES];
> drivers/net/wireless/ath/ath9k/dfs.c: if (num_fft_packets < (FFT_NUM_SAMPLES)) {
> drivers/net/wireless/ath/ath9k/dfs.c: for (i = 0; i < FFT_NUM_SAMPLES; i++)
> drivers/net/wireless/ath/ath9k/dfs.c: if (num_fft_packets < (FFT_NUM_SAMPLES)) {
> drivers/net/wireless/ath/ath9k/dfs.c: for (i = 0; i < FFT_NUM_SAMPLES; i++)