Pull up following revision(s) (requested by msaitoh in ticket #803):


----------------------------
revision 1.251
date: 2013/02/01 15:02:31;  author: matt;  state: Exp;  lines: +45 -24
cleanup PVF_WRITE & pvh_attrs interaction.
----------------------------
revision 1.250
date: 2013/01/31 22:01:49;  author: skrll;  state: Exp;  lines: +3 -3
Another typo in a comment.
----------------------------
revision 1.249
date: 2013/01/31 21:57:39;  author: skrll;  state: Exp;  lines: +3 -3
Typo in comment.
----------------------------
revision 1.247
date: 2013/01/11 12:04:00;  author: matt;  state: Exp;  lines: +13 -5
Fix a bug in pmap_modify_pv where we didnt set PVF_WRITE on a page after
changing its mapping to writeable.
Add more KASSERTS
Dont go into DDB by default in pmap_fixup.
----------------------------
revision 1.243
date: 2012/12/10 06:54:23;  author: matt;  state: Exp;  lines: +5 -3
Change a KASSERT to a KASSERTMSG
----------------------------
revision 1.233
date: 2012/08/29 17:08:41;  author: matt;  state: Exp;  lines: +4 -4
Support PMAP_NOCACHE in pmap_kenter_pa
----------------------------
revision 1.232
date: 2012/08/29 05:51:30;  author: matt;  state: Exp;  lines: +3 -3
Use the correct prot mask in vector_page_setprot
----------------------------
Ticket 803.