Subject: Re: [PATCH] rtlwifi: Remove unnecessary NULL check in rtl_regd_init

From: Pkshih <[email-masked]>
Date: Wed, 23 Oct 2019 05:38:30 +0000

On Tue, 2019-10-22 at 17:47 -0700, Nathan Chancellor wrote:
> When building with Clang + -Wtautological-pointer-compare:
> 
> drivers/net/wireless/realtek/rtlwifi/regd.c:389:33: warning: comparison
> of address of 'rtlpriv->regd' equal to a null pointer is always false
> [-Wtautological-pointer-compare]
>         if (wiphy == NULL || &rtlpriv->regd == NULL)
>                               ~~~~~~~~~^~~~    ~~~~
> 1 warning generated.
> 
> The address of an array member is never NULL unless it is the first
> struct member so remove the unnecessary check. This was addressed in
> the staging version of the driver in commit f986978b32b3 ("Staging:
> rtlwifi: remove unnecessary NULL check").
> 
> While we are here, fix the following checkpatch warning:
> 
> CHECK: Comparison to NULL could be written "!wiphy"
> 35: FILE: drivers/net/wireless/realtek/rtlwifi/regd.c:389:
> +       if (wiphy == NULL)
> 
> Fixes: 0c8173385e54 ("rtl8192ce: Add new driver")
> Link:https://github.com/ClangBuiltLinux/linux/issues/750
> Signed-off-by: Nathan Chancellor <[email-masked]>

Looks good.
Thanks for your fix.

Acked-by: Ping-Ke Shih <[email-masked]>

> ---
>  drivers/net/wireless/realtek/rtlwifi/regd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/realtek/rtlwifi/regd.c
> b/drivers/net/wireless/realtek/rtlwifi/regd.c
> index c10432cd703e..8be31e0ad878 100644
> --- a/drivers/net/wireless/realtek/rtlwifi/regd.c
> +++ b/drivers/net/wireless/realtek/rtlwifi/regd.c
> @@ -386,7 +386,7 @@ int rtl_regd_init(struct ieee80211_hw *hw,
>  	struct wiphy *wiphy = hw->wiphy;
>  	struct country_code_to_enum_rd *country = NULL;
>  
> -	if (wiphy == NULL || &rtlpriv->regd == NULL)
> +	if (!wiphy)
>  		return -EINVAL;
>  
>  	/* init country_code from efuse channel plan */