On Thu, 15 Apr 1999 19:31:47 +0200 (IST), "Peter L. Peres" <[EMAIL PROTECTED]>
wrote:
>There are such things as 'double faults' and 'triple faults'. A triple
>fault shuts down the CPU (or resets it ?) afaik. Udi ? ;)
Dragging me in had cost me 30 minutes of search time on Intel CD's...
Yes, triple faults shuts down the CPU. (not that I knew this before searching
the CD).
A single fault is legitimate (page miss, page fault by a user process,
floating point exception, etc.).
A double fault is usually more destructive, and happenes when you get an
exception while you are already handling an exception. In x86 architecture,
the possible exceptions are divided into 3 groups, Benign, Contributory, and
Page faults.
Exception behavior on double fault depends on the combination of the current
exception group being handled, and the new exception group. The possible
options are either handling the new exception serially (i.e. after the first
one terminates), or generate a double fault.
>Double and triple faults are only common in OS and firmware development
><g>.
As long as it's during *development* ;-)
>Peter
Udi
