Re: [PATCH net v2 3/3] rtase: Fix a type error in min_t

[David Laight <david.laight.linux@gmail.com>]

On Wed, 16 Apr 2025 20:45:34 +0800
Justin Lai <justinlai0215@realtek.com> wrote:

> Fix a type error in min_t.

NAK, in particular u16 is likely to be buggy
Consider what would happen if RTBASE_MITI_MAX_PKT_NUM was 65536.
(Yes, I know that isn't the intent of the code...)

As pointed out earlier using min() shouldn't generate a compile warning
and won't mask off significant bits.

Also I think it isn't a bug in any sense because the two functions
have a single caller that passes a constant.

	David


> 
> Fixes: a36e9f5cfe9e ("rtase: Add support for a pci table in this module")
> Signed-off-by: Justin Lai <justinlai0215@realtek.com>
> ---
>  drivers/net/ethernet/realtek/rtase/rtase_main.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/realtek/rtase/rtase_main.c b/drivers/net/ethernet/realtek/rtase/rtase_main.c
> index 55b8d3666153..bc856fb3d6f3 100644
> --- a/drivers/net/ethernet/realtek/rtase/rtase_main.c
> +++ b/drivers/net/ethernet/realtek/rtase/rtase_main.c
> @@ -1923,7 +1923,7 @@ static u16 rtase_calc_time_mitigation(u32 time_us)
>  	u8 msb, time_count, time_unit;
>  	u16 int_miti;
>  
> -	time_us = min_t(int, time_us, RTASE_MITI_MAX_TIME);
> +	time_us = min_t(u32, time_us, RTASE_MITI_MAX_TIME);
>  
>  	if (time_us > RTASE_MITI_TIME_COUNT_MASK) {
>  		msb = fls(time_us);
> @@ -1945,7 +1945,7 @@ static u16 rtase_calc_packet_num_mitigation(u16 pkt_num)
>  	u8 msb, pkt_num_count, pkt_num_unit;
>  	u16 int_miti;
>  
> -	pkt_num = min_t(int, pkt_num, RTASE_MITI_MAX_PKT_NUM);
> +	pkt_num = min_t(u16, pkt_num, RTASE_MITI_MAX_PKT_NUM);
>  
>  	if (pkt_num > 60) {
>  		pkt_num_unit = RTASE_MITI_MAX_PKT_NUM_IDX;