Re: [PATCH] x86/kexec: use pr_err() instead of kexec_dprintk() when an error occurs

[Andrew Morton]

On Tue, 19 Dec 2023 15:29:01 +0800 Yuntao Wang <ytcoode@xxxxxxxxx> wrote:

> When an error is detected, use pr_err() instead of kexec_dprintk() to
> output log message.
>
> In addition, remove the unnecessary return from set_page_address().

The above describes what the code does, which is already quite clear
from looking at the code.

Please write changelogs and code comments which describe *why* the code
does something, rather than *what* it does.

>
>
> --- a/arch/x86/kernel/kexec-bzimage64.c
> +++ b/arch/x86/kernel/kexec-bzimage64.c
> @@ -429,7 +429,7 @@ static void *bzImage64_load(struct kimage *image, char *kernel,
>  	 * command line. Make sure it does not overflow
>  	 */
>  	if (cmdline_len + MAX_ELFCOREHDR_STR_LEN > header->cmdline_size) {
> -		kexec_dprintk("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");
> +		pr_err("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");

ie, what are the reasons for this change?

>  		return ERR_PTR(-EINVAL);
>  	}
>  
> diff --git a/mm/highmem.c b/mm/highmem.c
> index e19269093a93..bd48ba445dd4 100644
> --- a/mm/highmem.c
> +++ b/mm/highmem.c
> @@ -799,8 +799,6 @@ void set_page_address(struct page *page, void *virtual)
>  		}
>  		spin_unlock_irqrestore(&pas->lock, flags);
>  	}
> -
> -	return;
>  }
>  
>  void __init page_address_init(void)
> -- 
> 2.43.0