PAE on -current pitfalls and issues?

Peter Wemm peter at
Tue Jun 15 20:58:44 GMT 2004

On Tuesday 15 June 2004 05:55 am, Daniel Lang wrote:
> Hi again,
> Daniel Lang wrote on Tue, Jun 15, 2004 at 02:46:05PM +0200:
> [..]
> > - Do I need to include 'options PAE' somehow into the
> >   build of the kernel-modules in order to use them?
> >   Or is a pure static kernel the only option?
> I just stumbled across the handbook section about PAE,
> so this says modules are not working. I assume this is
> still the case.

There's a gotcha with KVA_PAGES.  On a standard kernel, there are 1024 
Page directory slots.  By default we use 256 of them for 1 out of 4GB.

On a PAE kernel, there are now 2048 page directory slots.  The same 1:3 
split requires a default KVA_PAGES of 512.  So if you want to increase 
KVA beyond the default 1GB, do not forget to take the scaling into 

> Cheers,
>  Daniel

Peter Wemm - peter at; peter at; peter at
"All of this is for nothing if we don't go to the stars" - JMS/B5

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