Re: [PATCH net-next 4/7] net: hibmcge: Add register dump supported in this module

[Jijie Shao <shaojijie@huawei.com>]

on 2024/10/23 21:42, Jijie Shao wrote:
>   
> +#define HBG_REG_NAEM_MAX_LEN	24
> +#define HBG_REG_TYPE_MAX_LEN	8

......

> +
> +struct hbg_reg_offset_name_map {
> +	u32 reg_offset;
> +	char name[HBG_REG_NAEM_MAX_LEN];
> +};
> +
> +struct hbg_reg_type_info {
> +	char name[HBG_REG_TYPE_MAX_LEN];
> +	u32 offset_base;
> +	const struct hbg_reg_offset_name_map *reg_maps;
> +	u32 reg_num;
> +};
> +
> +struct hbg_reg_info {
> +	char name[HBG_REG_NAEM_MAX_LEN + HBG_REG_TYPE_MAX_LEN];
> +	u32 offset;
> +	u32 val;

......

> +
> +static u32 hbg_get_reg_info(struct hbg_priv *priv,
> +			    const struct hbg_reg_type_info *type_info,
> +			    const struct hbg_reg_offset_name_map *reg_map,
> +			    struct hbg_reg_info *info)
> +{
> +	info->val = hbg_reg_read(priv, reg_map->reg_offset);
> +	info->offset = reg_map->reg_offset - type_info->offset_base;
> +	snprintf(info->name, sizeof(info->name),
> +		 "[%s] %s", type_info->name, reg_map->name);
> +

In addition, there are compilation warning here:
../drivers/net/ethernet/hisilicon/hibmcge/hbg_ethtool.c: In function ‘hbg_ethtool_get_regs’:
../drivers/net/ethernet/hisilicon/hibmcge/hbg_ethtool.c:322:20: warning: ‘%s’ directive output may be truncated writing up to 127 bytes into a region of size 31 [-Wformat-truncation=]
   322 |                  "[%s] %s", type_info->name, reg_map->name);
       |                    ^~
In function ‘hbg_get_reg_info’,
     inlined from ‘hbg_ethtool_get_regs’ at ../drivers/net/ethernet/hisilicon/hibmcge/hbg_ethtool.c:338:14:
../drivers/net/ethernet/hisilicon/hibmcge/hbg_ethtool.c:321:9: note: ‘snprintf’ output between 4 and 154 bytes into a destination of size 32
   321 |         snprintf(info->name, sizeof(info->name),
       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   322 |                  "[%s] %s", type_info->name, reg_map->name);


But in fact, sizeof(info->name) is (24+8), type_info->name length is 8, and reg_map->name length is 24.
I understand that it should be fine to use here.

Thanks,
Jijie Shao