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Date: Wed, 7 Mar 2001 13:56:39 -0300 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Manfred Spraul <manfred@colorfullife.com>
cc: <linux-kernel@vger.kernel.org>
Subject: Re: BUG? race between kswapd and ptrace (access_process_vm )
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On Wed, 7 Mar 2001, Manfred Spraul wrote:

> Is kswapd now running without lock_kernel()?

Indeed ...

> Then there is a race between swapout and ptrace:
> access_process_vm() accesses the page table entries, only protected with
> the mmap_sem semaphore and lock_kernel().
>
> Isn't
>
>     spin_lock(&mm->page_table_lock);
>
> missing in access_one_page() [in linux/kernel/ptrace.c]?

You're probably right here ...

regards,

Rik
--
Linux MM bugzilla: http://linux-mm.org/bugzilla.shtml

Virtual memory is like a game you can't win;
However, without VM there's truly nothing to lose...

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