Re: Why can't we use the user-space pointer in kernel mode?

["srinivas bakki" <srinivas.bakki@xxxxxxxxx>]

On 5/3/06, cheng long <kevinclcn@xxxxxxxxx> wrote:

Hi, all

Since the progress in kernel mode can access the whole address space,
why we must copy the user-space data into kernel space?
Why  can't we dereference the user-space pointer directly?

Thanks,
Regards,
Cheng

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since the mapping is quite different. the way kernel accesses the entire system memory is much different than how the user space memory is accessed.

 

This has been discussed long back, u can have a look at the threads posted.