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Subject: Re: [PATCH v2] kallsyms: Remove function arch_get_kallsym()
To:     Jiapeng Chong <jiapeng.chong@linux.alibaba.com>, <ast@kernel.org>
CC:     <daniel@iogearbox.net>, <andrii@kernel.org>, <kafai@fb.com>,
        <songliubraving@fb.com>, <john.fastabend@gmail.com>,
        <kpsingh@kernel.org>, <linux-kernel@vger.kernel.org>,
        <netdev@vger.kernel.org>, <bpf@vger.kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>
References: <1619084946-28509-1-git-send-email-jiapeng.chong@linux.alibaba.com>
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On 4/22/21 2:49 AM, Jiapeng Chong wrote:
> Fix the following sparse warning:
> 
> kernel/kallsyms.c:457:12: warning: symbol 'arch_get_kallsym' was not
> declared. Should it be static?
> 
> Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
> ---
> Changes in v2:
>    -Remove function arch_get_kallsym().
> 
>   kernel/kallsyms.c | 18 ++----------------
>   1 file changed, 2 insertions(+), 16 deletions(-)
> 
> diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
> index 8043a90..49c4268 100644
> --- a/kernel/kallsyms.c
> +++ b/kernel/kallsyms.c
> @@ -454,24 +454,10 @@ struct kallsym_iter {
>   	int show_value;
>   };
>   
> -int __weak arch_get_kallsym(unsigned int symnum, unsigned long *value,
> -			    char *type, char *name)
> -{
> -	return -EINVAL;
> -}

This is originally added by
   d83212d5dd67 kallsyms, x86: Export addresses of PTI entry trampolines
by Alexander Shishkin.
The original patch has a x86 specific implementation but later
it is removed.

Maybe Alexander Shishkin can take a look?

> -
>   static int get_ksymbol_arch(struct kallsym_iter *iter)
>   {
> -	int ret = arch_get_kallsym(iter->pos - kallsyms_num_syms,
> -				   &iter->value, &iter->type,
> -				   iter->name);
> -
> -	if (ret < 0) {
> -		iter->pos_arch_end = iter->pos;
> -		return 0;
> -	}
> -
> -	return 1;
> +	iter->pos_arch_end = iter->pos;
> +	return 0;
>   }
>   
>   static int get_ksymbol_mod(struct kallsym_iter *iter)
>