Another pmap related panic

[Alan L. Cox]

Mark Tinguely wrote:
> 
> It could be a memory problem. Could you also please apply an assert
> to pmap_enter_quick() + INVARIANTS. This is a quick test that checks
> all the other paths that call pmap_enter_quick() are locked out so
> that two processors cannot be using the PADDR1/PMAP1 at the same time.
> 

Neither of Lukas's panics suggests that PADDR1/PMAP1 is being used.  The
faulting virtual addresses are

fault virtual address   = 0xbfca1974

and

fault virtual address   = 0xbfcadf10

which are within the PTmap, not PADDR1.  In other words,
pmap_pte_quick() concluded that the given pmap was currently active and
therefore the pte was accessible through the mapping that each address
space has to its own page table.

Regards,
Alan