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Date: Thu, 28 Dec 2006 10:49:23 +0000
From: Russell King <rmk+lkml@arm.linux.org.uk>
To: Martin Michlmayr <tbm@cyrius.com>
Cc: Gordon Farquharson <gordonfarquharson@gmail.com>,
       Linus Torvalds <torvalds@osdl.org>, David Miller <davem@davemloft.net>,
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       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm: fix page_mkclean_one
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On Thu, Dec 28, 2006 at 11:16:59AM +0100, Martin Michlmayr wrote:
> * Gordon Farquharson <gordonfarquharson@gmail.com> [2006-12-27 22:38]:
> > >> #define TARGETSIZE (100 << 12)
> > >
> > >That's just 400kB!
> > >
> > >There's no way you should see corruption with that kind of value. It
> > >should all stay solidly in the cache.
> > >
> > >Is this perhaps with ARM nommu or something else strange? It may be that
> > >the program just doesn't work at all if mmap() is faked out with a malloc
> > >or similar.
> > 
> > Definitely a question for the ARM gurus. I'm out of my depth.
> 
> By the way, I just tried it with TARGETSIZE (100 << 12) on a different
> ARM machine (a Thecus N2100 based on an IOP32x chip with 128 MB of
> memory) and I see similar results to that from Gordon:

Work around the glibc memset() problem by passing nr & 255, and re-run
the test.  You're getting false positives.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of: