On Apr 28, 2008, at 12:04 PM, Scott Wood wrote:

On Mon, Apr 28, 2008 at 11:58:58AM -0500, Kumar Gala wrote:

quoted

On Apr 28, 2008, at 10:59 AM, Scott Wood wrote:

quoted

On Mon, Apr 28, 2008 at 10:40:56AM -0500, Kumar Gala wrote:

quoted

A few possibilities:
* introduce an additional function pointer as part of
EXC_XFER_TEMPLATE() to specifies the type of handler (normal, crit,
dbg, mcheck)
* use the traps field low order bits to determine normal, crit,  
dbg,
mcheck at run time.
* duplicate the code paths for each exception level

suggestions?

You could temporarily disable all asynchronous exceptions, and use  
the
registers of the highest-priority exception type.

That doesn't work.  We have NMIs or will have them in the future.

Truly non-maskable?  Ick.  You could have a separate code path just  
for
the exception type that NMIs use, I guess, if there's a clear
highest-priority among the remaining interrupt types.  What sort of
exceptions are they?

The NMIs are machine check only so a separate path for them isn't a  
terrible idea.

However, disabling all other interrupts seems worse than adding a  
function pointer.

- k