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From: David Howells <dhowells@redhat.com>
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To: Mark Moseley <moseleymark@gmail.com>
Cc: dhowells@redhat.com,
        Linux filesystem caching discussion list 
	<linux-cachefs@redhat.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [Linux-cachefs] 3.0.3 64-bit Crash running fscache/cachefilesd
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Date: Wed, 12 Oct 2011 10:26:30 +0100
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Mark Moseley <moseleymark@gmail.com> wrote:

> >> [37818.485559] kernel BUG at fs/fscache/object-list.c:64!
> >
> > Hmmm...  An object is being added to the object list twice.  It may
> > indicate a free before an object is finished with.  Do you have slab
> > debugging turned on?
>
> It's compiled in but not currently enabled. Should I do so?

It can't be turned on or off dynamically.  If CONFIG_DEBUG_SLAB is enabled, then
it's switched on.

> And anything I should be looking for in it?

The BUG that you encountered would suggest a piece of memory is still in use as
far as parts of fscache is concerned - but it's just been produced by the slab
allocator again.  This is the sort of thing the slab debugger might catch.

David