Re: process address space

["Samiullah Khawaja" <sami.khawaja@xxxxxxxxx>]

yes it is not accessible because all those pages are marked as not user level pages in page tables of that process.

On Wed, Nov 19, 2008 at 9:41 PM, Michael Blizek <michi1@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

Hi!

On 15:40 Tue 18 Nov     , ruby wrote:
> For each process's address space, in addition to its own code, data,
> shared library code and data etc. are there any kernel code in it? that
> doesn't make much sense.

No, the "kernel" part of the address space is not accessable in user space.
It is just the physical memory mapped into the address space as a big chunk.
The purpose is that user-space/kernel space switches (e.g. due to system calls
do not require a rather expensive (TLB flush) address space switch.
       -Michi
--
programing a layer 3+4 network protocol for mesh networks
see http://michaelblizek.twilightparadox.com

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Samiullah Khawaja
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