Peter Wemm 85b23d1138 Fix an evil bug that appeared in September 2003. VM86 bios calls use two
of the __pcb_spare longs.  Except that fields were changed and one of the
spare values was used and the __pcb_spare field was reduced from two to one
long.  Now VM86 bios calls can trash the first 4 bytes of the next page
following the kernel stack/pcb.  This Is Bad(TM).  This bug has been
present in 5.2-release and onwards, and is still in RELENG_5.

Instead of tempting fate and trying to use "spare" fields, explicitly
reserve them.
2005-04-13 18:13:40 +00:00
..