From: Paul Mackerras <paulus@samba.org>
Subject: Re: Crash (ext3 ) during 2.6.29-rc6 boot
Date: Mon, 23 Feb 2009 21:32:47 +1100
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Cc: Jan Kara <jack@ucw.cz>, Mel Gorman <mel@csn.ul.ie>,
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	linuxppc-dev@ozlabs.org, linux-ext4@vger.kernel.org
To: Andrew Morton <akpm@linux-foundation.org>
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Andrew Morton writes:

> It looks like we died in ext3_xattr_block_get():
> 
> 		memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
> 		       size);
> 
> Perhaps entry->e_value_offs is no good.  I wonder if the filesystem is
> corrupted and this snuck through the defenses.
> 
> I also wonder if there is enough info in that trace for a ppc person to
> be able to determine whether the faulting address is in the source or
> destination of the memcpy() (please)?

It appears to have faulted on a load, implicating the source.  The
address being referenced (0xc00000003f380000) doesn't look
outlandish.  I wonder if this kernel has CONFIG_DEBUG_PAGEALLOC turned
on, and what page size is selected?

Paul.