Re: Athlon/AGP issue update

Val Henson
2002-01-25T18:18:01Z

On Wed, Jan 23, 2002 at 06:14:33PM -0500, Albert D. Cahalan wrote:
>
> It's a waste to use BAT mappings for the kernel anyway, because
> we try to keep the huge computations and graphics in userspace.
> With page tables under BAT mappings, privileged user code could
> be allowed to steal BAT registers for locked memory or IO memory.

The rationale behind BAT mapping the kernel is that the kernel does not
use any TLB entries, leaving them all for user processes. (As long as
we have < 512MB RAM.)

-VAL