
- havent seen any kernel panics yet, but lots of application crashes.
   I tagged a bunch of them but there is still weirdness for example
   when doing multiple concurrent mk cleans.

- the compiler does not 8-byte align vlong/uvlongs.  Because of this
   there is some code in l.s that writes these in two-halves rather
   than a single 8-byte write.  Should be fixed when the compiler is
   updated.
- we dont make use of the FP dirty bits.  Doing so could possibly
   simplify FP active/inactive handling.
- when we go MP, are we sharing mmu ctx across processors?  If
   so we will have to be more careful during ctx dealloc!
- still using TSO.  should eventually support a higher performance ordering.

- seperating traps and interrupts would be more efficient --
   especially fast-tracking the linear mapping of RAM above KZERO
   and the remapping of 0x60 interrupts to softints.
	- should have a fast trap handler for 0x60, remapping softint.
	- should have trap entries for each different way of getting
	   a fault addr, jump to a common handler which replaces
	   kernel tlb on fast path, otherwise vectors to normal handler.
- traps are a mess right now.  rethink after we get everything figured out.
- traplinks are very simplistic.  We could tweak some performance here
   if we needed it.
- hme ethernet keeps a fixed number of buffers for the hardware and copies
   data into and out of them.  Would be better to not allocate any xmit
   buffers and simply xfer the ones given to us in-place.  Similarly would
   be good to be smarter about the receive buffers.


TODO
- true 64bit compiler support and kernel support.
- graphics, keyboard, normal console.
- scsi
- SMP
