cvs commit: src/sys/i386/i386 genassym.c vm86bios.s src/sys/i386/include pcb.h

[Peter Wemm]

peter       2005-04-13 18:13:40 UTC

  FreeBSD src repository

  Modified files:
    sys/i386/i386        genassym.c vm86bios.s 
    sys/i386/include     pcb.h 
  Log:
  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.
  
  Revision  Changes    Path
  1.150     +1 -1      src/sys/i386/i386/genassym.c
  1.31      +2 -2      src/sys/i386/i386/vm86bios.s
  1.53      +1 -1      src/sys/i386/include/pcb.h