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Subject: Re: [PATCH/RFC] oops and panic message logging to MTD
From: Richard Purdie <richard@openedhand.com>
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Date: Tue, 29 May 2007 13:35:06 +0100
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On Tue, 2007-05-29 at 13:32 +0100, Richard Purdie wrote:
> Kernel oops and panic messages are invaluable when debugging crashes.
> These messages often don't make it to flash based logging methods (say a
> syslog on jffs2) due to the overheads involved in writing to flash.
> 
> This patch allows you to turn an MTD partition into a circular log
> buffer where kernel oops and panic messages are written to. The messages
> are obtained by registering a console driver and checking
> oops_in_progress. Erases are performed in advance to maximise the
> chances of a saving messages.
> 
> To activate it, add console=ttyMTDx to the kernel commandline (where x
> is the mtd device number to use).
> 
> Signed-off-by: Richard Purdie <rpurdie@openedhand.com>

I meant to add, http://folks.o-hand.com/richard/oopslog.c is an example
of extracting this information in userspace. It will work with an
mtdblock device or a dump of the mtd partition.

Cheers,

Richard