Date: Fri, 27 Oct 2006 21:50:37 -0700
From: Andrew Morton <akpm@osdl.org>
To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Pavel Machek <pavel@ucw.cz>, Rusty Russell <rusty@rustcorp.com.au>,
       virtualization <virtualization@lists.osdl.org>,
       lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/4] Prep for paravirt: Be careful about touching BIOS
 address space
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On Fri, 27 Oct 2006 21:33:08 -0700
Jeremy Fitzhardinge <jeremy@goop.org> wrote:

> Andrew Morton wrote:
> > It'd be better to use include/linux/uaccess.h:probe_kernel_address() for
> > this operation.
> >   
> Ah, yes, that was the precedent I was thinking of,

We've done open-coded __get_user() in various places in the past.  The difference with
probe_kernel_address() is that it doesn't get deadlocked on mmap_sem().

>  but I guess it would 
> be better to just use it directly.  It's a relatively new interface, 
> isn't it?

Yeah.  New enough that nobody's tried using it on non-x86 ;) It needs
to do set_fs(KERNEL_DS).

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