[PATCH 01/16] net/hns3: fix possible truncation of hash key when config

[Ferruh Yigit]

On 3/10/2023 9:35 AM, Dongdong Liu wrote:
> From: Huisong Li <lihuisong at huawei.com>
> 
> The hash key length of hns3 driver is obtained from firmware. If the
> length isn't a multiple of HNS3_RSS_HASH_KEY_NUM (16), the last part
> of hash key will be truncated.
> 

I am not sure if the explanation is correct, according below code last
part of the key is truncated if key_len *is* multiple of
HNS3_RSS_HASH_KEY_NUM.

Because code assumes "key_len % HNS3_RSS_HASH_KEY_NUM" will give the
remaining part of the key, but when key_len is multiple of
HNS3_RSS_HASH_KEY_NUM it gives 0, causing last HNS3_RSS_HASH_KEY_NUM
chunk truncated.

If above understanding correct, I can fix commit log while merging.

> Fixes: 4a7384e3c34d ("net/hns3: refactor set RSS hash algorithm and key interface")
> Fixes: c37ca66f2b27 ("net/hns3: support RSS")
> Cc: stable at dpdk.org
> 

I am not sure if `c37ca66f2b27 ("net/hns3: support RSS")` is needed
here, issue seems because of commit 4a7384e3c34d, so this should be:

Fixes: 4a7384e3c34d ("net/hns3: refactor set RSS hash algorithm and key
interface")
Cc: stable at dpdk.org


> Signed-off-by: Huisong Li <lihuisong at huawei.com>
> Signed-off-by: Dongdong Liu <liudongdong3 at huawei.com>
> ---
>  drivers/net/hns3/hns3_rss.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/hns3/hns3_rss.c b/drivers/net/hns3/hns3_rss.c
> index d6e0754273..2011c18b9b 100644
> --- a/drivers/net/hns3/hns3_rss.c
> +++ b/drivers/net/hns3/hns3_rss.c
> @@ -301,7 +301,8 @@ hns3_rss_set_algo_key(struct hns3_hw *hw, uint8_t hash_algo,
>  		req->hash_config |= (hash_algo & HNS3_RSS_HASH_ALGO_MASK);
>  		req->hash_config |= (idx << HNS3_RSS_HASH_KEY_OFFSET_B);
>  
> -		if (idx == max_bd_num - 1)
> +		if (idx == max_bd_num - 1 &&
> +		    (key_len % HNS3_RSS_HASH_KEY_NUM) != 0)
>  			cur_key_size = key_len % HNS3_RSS_HASH_KEY_NUM;
>  		else
>  			cur_key_size = HNS3_RSS_HASH_KEY_NUM;