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To: linux-kernel@vger.kernel.org
From: torvalds@transmeta.com (Linus Torvalds)
Subject: Re: [patch] 'sticky pages' support in the VM, futex-2.5.38-C5
Date: Thu, 26 Sep 2002 15:01:51 +0000 (UTC)
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In article <Pine.LNX.4.44.0209261311070.11487-100000@localhost.localdomain>,
Ingo Molnar  <mingo@elte.hu> wrote:
>
>while running fork() testcases with NPTL we found a number of futex
>related failures that i tracked down to the following conceptual bug in
>the futex code:

This patch seems trivially broken by having two futexes on the same
page.  When the first futex removes itself, it will clear the sticky
bit, even though the other futex is still pinning the same page.

Trust me, you'll have to use the page list approach.

		Linus
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