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Date: Fri, 1 Jun 2007 17:16:12 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Christoph Lameter <clameter@sgi.com>,
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Subject: Re: [RFC] [PATCH] cpuset operations causes Badness at mm/slab.c:777
 warning
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On Fri, 1 Jun 2007 16:57:20 -0700 (PDT)
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> Andrew, want to take this patch to -mm to see if it triggers anything?

spose so.

I think it'd be better if we kept the WARN_ON_ONCE(size == 0) in there,
because it is exposing some coding warts.  But we should turn it off for
2.6.22 and make it conditional on CONFIG_DEVEL_KERNEL (or whatever it will
be called) later.

The BADPTR thing is a little worrying because it will make
previously-working-by-luck code go oops.  I guess we can live with that.

So we end up with the BADPTR code enabled even in production kernels, in
which case your ((unsigned long)x <= 16) trick is worth doing.