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Date: Tue, 19 Dec 2023 12:21:51 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Yuntao Wang <ytcoode@gmail.com>
Cc: bhe@redhat.com, bp@alien8.de, corbet@lwn.net,
 dave.hansen@linux.intel.com, ebiederm@xmission.com, hpa@zytor.com,
 kexec@lists.infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com,
 tglx@linutronix.de, x86@kernel.org
Subject: Re: [PATCH] x86/kexec: use pr_err() instead of kexec_dprintk() when
 an error occurs
Message-Id: <20231219122151.aa4ae562537abf74067588fe@linux-foundation.org>
In-Reply-To: <20231219072902.90104-1-ytcoode@gmail.com>
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	<20231219072902.90104-1-ytcoode@gmail.com>
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On Tue, 19 Dec 2023 15:29:01 +0800 Yuntao Wang <ytcoode@gmail.com> 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