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Date: Mon, 23 Feb 2009 09:24:39 +0100
Message-ID: <19f34abd0902230024g63aadad2jef16c97a9d792291@mail.gmail.com>
Subject: Re: [PATCH] mm: fix lazy vmap purging (use-after-free error)
From: Vegard Nossum <vegard.nossum@gmail.com>
To: paulmck@linux.vnet.ibm.com
Cc: Ingo Molnar <mingo@elte.hu>, stable@kernel.org,
       Andrew Morton <akpm@linux-foundation.org>,
       Nick Piggin <npiggin@suse.de>, Pekka Enberg <penberg@cs.helsinki.fi>,
       linux-kernel@vger.kernel.org
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2009/2/23 Paul E. McKenney <paulmck@linux.vnet.ibm.com>:
> Hello, Vegard,
>
> Could you please try out the following patch?  I am not 100% confident
> of it on non-x86 architectures, nor during the time that non-boot CPUs
> start up (though this patch should not break non-boot CPUs any more than
> they might already be broken).

Hi!

This patch fixes it for me. Now I see the huge stream of call_rcu()s,
followed by a huge stream of kfrees() (after the list traversal has
completed).


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036