> > BSDI seems to be able to handle the problem in software. No source
> > provided as of today.
>
> Dumping the idt and page tables on a running BSDI box with the patch answers
> how its done however.
>
> The IDT points to the end of a page such that vector 0x0E (page fault) is
> the start of the next page. The page with vectors 0-0xD is missing. This
> will cause all traps to cause a page fault. One assumes the page fault
> handler then fixes them up and handles them
>
> Alan
What kind of performance hit is this?