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Date: Fri, 18 Feb 2011 08:40:15 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Mike Travis <travis@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Len Brown <len.brown@intel.com>, Yinghai Lu <yhlu.kernel@gmail.com>,
        linux-acpi@vger.kernel.org, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/5] printk: Allocate kernel log buffer earlier
Message-ID: <20110218074015.GG11404@elte.hu>
References: <20110217185131.960038922@gulag1.americas.sgi.com>
 <20110217185132.735139933@gulag1.americas.sgi.com>
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* Mike Travis <travis@sgi.com> wrote:

> +++ linux/kernel/printk.c
> @@ -162,46 +162,65 @@ void log_buf_kexec_setup(void)
>  }
>  #endif
>  
> +static unsigned long __initdata new_log_buf_len;
>  static int __init log_buf_len_setup(char *str)
>  {

Can you see the readability problem this new line introduces?

> +	char first_line[64], *first_nl;

The value 64 looks arbitrary. Needs to be symbolized and explained. (That would also 
make the sizeof(first_line) usage more readable later on.)

> +	pr_info("log_buf_len: %d, first line: %s\n",
> +		log_buf_len, first_line);

It's not just arbitrarily sized, but i dont see where it's guaranteed that it's a 
nil delimited string.

> +	pr_debug("bu: %d/%d (%d%%)\n",
> +		dest_idx, __LOG_BUF_LEN - dest_idx,
> +		(dest_idx * 100) / __LOG_BUF_LEN);

What's that?

Patch looks pretty ad-hoc. No comments whatsoever what the intention is either, so 
the reader has to go figure out the code.

Thanks,

	Ingo