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Date: Tue, 7 Oct 2008 11:18:24 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
cc: Matt Mackall <mpm@selenic.com>,
       Christoph Lameter <cl@linux-foundation.org>,
       linux-mm <linux-mm@kvack.org>, Nick Piggin <nickpiggin@yahoo.com.au>,
       Ingo Molnar <mingo@elte.hu>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       akpm <akpm@linuxfoundation.org>,
       Pekka J Enberg <penberg@cs.helsinki.fi>
Subject: Re: [BUG] SLOB's krealloc() seems bust
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On Tue, 7 Oct 2008, Peter Zijlstra wrote:

> On Tue, 2008-10-07 at 10:57 -0700, Linus Torvalds wrote:
> 
> > Peter - can you check with that
> > 
> > >  	if (slob_page(sp))
> > > -		return ((slob_t *)block - 1)->units + SLOB_UNIT;
> > > +		return (((slob_t *)block - 1)->units - 1) * SLOB_UNIT;
> > 
> > thing using
> > 
> > -		return ((slob_t *)block - 1)->units + SLOB_UNIT;
> > +		return ((slob_t *)block - 1)->units * SLOB_UNIT;
> > 
> > instead? 
> 
> went splat on the second run...

Well, that makes it simple. I'll take Matt's patch as being "tested", and 
somebody can hopefully explain where the extra unit comes from later.

			Linus