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Date: Fri, 4 Oct 2002 23:47:06 +0100
From: Jamie Lokier <lk@tantalophile.demon.co.uk>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@transmeta.com>, Andrew Morton <akpm@zip.com.au>,
       Rusty Russell <rusty@rustcorp.com.au>, linux-kernel@vger.kernel.org
Subject: Re: [patch] 'sticky pages' support in the VM, futex-2.5.38-C5
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Ingo Molnar wrote:
> futexes were not really designed with COW in mind - they were designed
> to be used in non-COW shared memory. This is a very bad limitation

I thought that futex-based locks were only reliable with PROT_SEM
memory, for architectures that define PROT_SEM (e.g. PPC) -- because of
the need for locking primitives to work in a cache coherent manner.

Is this not so?

-- Jamie
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