From: David Mosberger <davidm@napali.hpl.hp.com>
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Date: Fri, 26 Mar 2004 12:25:03 -0800
To: Andrew Morton <akpm@osdl.org>
Cc: davidm@hpl.hp.com, davidm@napali.hpl.hp.com, davej@redhat.com,
       mpm@selenic.com, linux-kernel@vger.kernel.org
Subject: Re: Fw: potential /dev/urandom scalability improvement
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>>>>> On Fri, 26 Mar 2004 10:49:04 -0800, Andrew Morton <akpm@osdl.org> said:

  Andrew> But the start address which is fed into prefetch_range() may
  Andrew> not be cacheline-aligned.  So if appropriately abused, a
  Andrew> prefetch_range() could wander off the end of the user's
  Andrew> buffer and into a new page.

  Andrew> I think this gets it right, but I probably screwed something
  Andrew> up.

Please, let's not make this more complicated than it is.  The
cacheline alignment doesn't matter at all.  Provided prefetch_range()
is given a range of guaranteed to be valid memory, then it will be
fine.  It never touches anything outside the specified range.

	--david
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