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Re: Virtual and Linear addresses

On 9/9/06, borasahin@xxxxxxxxxxx <borasahin@xxxxxxxxxxx> wrote: 

> i have a small question following the virtual kernel addresses issue -
>
> where does the kernel page tables stored ?
> is there a seperate place ?

swapper_pg_dir. Look at e.g. arch/i386/kernel/head.S...

> or are they part of each process' page tables (and equal in all of them) ?

Yes, that's true... 

Just to add a bit more of info (for IA32 specifically). Page Table
Entries have flags which indicate type/attributes of entries etc. One
such flag is the "Global" flag. If it is set, it means that the entry
is shared across processes. So a context switch will not discard those
entries from the TLB automatically (Can be flushed manually using the
INVPLG instruction though).


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Bora SAHIN

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Kernelnewbies: Help each other learn about the Linux kernel.
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