From: "H. Peter Anvin" <hpa@zytor.com>
To: Xin Tong <xerox.time.tech@gmail.com>
Cc: "Américo Wang" <xiyou.wangcong@gmail.com>,
linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: copy_*_user
Date: Sun, 23 Oct 2011 12:15:02 +0200 [thread overview]
Message-ID: <4EA3E926.80203@zytor.com> (raw)
In-Reply-To: <CALKntY0222DBU88W=j0Y2FpN7NRMSxmDk4XKy-m+keri4Gcu_A@mail.gmail.com>
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
next prev parent reply other threads:[~2011-10-23 10:15 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-10-22 17:06 copy_*_user Xin Tong
2011-10-23 2:50 ` copy_*_user Américo Wang
2011-10-23 9:23 ` copy_*_user Xin Tong
2011-10-23 10:15 ` H. Peter Anvin [this message]
2011-10-23 11:25 ` copy_*_user Xin Tong
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