[lkml]   [2011]   [Oct]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: copy_*_user
I do not remember, probably I was under the impression that kernel
accesses physical memory directly from my os course in college. So ,
the kernel access memory using the page table of the current process



On Sun, Oct 23, 2011 at 6:15 AM, H. Peter Anvin <> wrote:
> 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
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2011-10-23 13:27    [W:0.038 / U:5.068 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site