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Date: Tue, 7 Mar 2006 13:25:45 -0800
From: Andrew Morton <akpm@osdl.org>
To: Dean Roe <roe@sgi.com>
Cc: linux-kernel@vger.kernel.org, riel@redhat.com
Subject: Re: [PATCH] Prevent NULL pointer deref in grab_swap_token
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Dean Roe <roe@sgi.com> wrote:
>
> grab_swap_token() assumes that the current process has an mm struct,
> which is not true for kernel threads invoking get_user_pages().  Since
> this should be extremely rare, just return from grab_swap_token()
> without doing anything.
> 

Fair enough.

Which kernel threads are running get_user_pages()?