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Date: Sun, 23 Oct 2011 12:15:02 +0200
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Xin Tong <xerox.time.tech@gmail.com>
CC: =?ISO-8859-1?Q?Am=E9rico_Wang?= <xiyou.wangcong@gmail.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: copy_*_user
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On 10/23/2011 11:23 AM, Xin Tong wrote:
> I found that __copy_from_user_ll(void *to, const void __user *from,
> unsigned long n) eventually calls some asm which use mov and rep on
> the passed-in to & from pointers. This is in kernel mode and to & from
> are virtual addresses ? are not the kernel accessing physical RAM
> directly ( without pagetable ) ?

No.  What gave you that idea?

	-hpa