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Date: Mon, 18 Oct 2010 15:33:50 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: "simon.kagstrom@netinsight.net" <simon.kagstrom@netinsight.net>,
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	<dle-develop@lists.sourceforge.net>,
        Satoru Moriya <satoru.moriya@hds.com>
Subject: Re: [RFC][Patch] Adding kmsg_dump() to
 reboot/halt/poweroff/emergency_restart path
Message-Id: <20101018153350.18b68c50.akpm@linux-foundation.org>
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On Mon, 18 Oct 2010 18:24:11 -0400
Seiji Aguchi <seiji.aguchi@hds.com> wrote:

> Hi,
> 
> Final messages from reboot, halt and poweroff aren't output to disk because klogd/syslogd 
> has been killed and root file system has been turned read-only.
> 
> Final messages from emergency_restart aren't output to disk as well because system may
> reboot before klogd/syslogd outputs messages to disk.
> 
> Therefore, it is better to put kmsg_dumper in reboot/halt/poweroff/emergency_restart path.
> Any comments/advices are welcome.
> 

I don't get it.

What actual problem are we solving here?  Why is the current code
inadequate?  It would help to demonstrate some use-case and to explain
how the situation improved with this patch.