How to access system memory?

[ldp-discuss-request@lists.debian.org]

Dear all:

I want to write a program to read some bytes from memory
0xF000:0800(0XF0800) to 0xF000:0d00(0xf0d00) under LINUX, I know that I
should write a device drvier to read memory data, but some function as
memcpy_tofs and memcpy_fromfs are not define under asm/segment. and when I
direct read the address ,when i use "insmod mydrv", an error said
"segmentatin fault",and "unable to handle kernel paging request at virtual
address 000f0800".

how can I do

thanks very much!!!
Good Luck!

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Õźêΰ Hongwei Zhang
Office Tel.:(0755)2712288-8832
  pager    :191(2)-8113143
  Email    :zhanghwb@legend.com.cn

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