Re: DIE_GPF vs. DIE_PAGE_FAULT/DIE_TRAP

["Jan Beulich" <JBeulich@novell.com>]

>>> Andi Kleen <ak@suse.de> 26.10.05 17:50:44 >>>
>On Wednesday 26 October 2005 17:21, Jan Beulich wrote:
> 
>> Hmm, then this isn't really useful for a debugger. There ought to be
a
>> chance to filter exceptions early (i.e. debugger accesses to
non-mapped
>> memory or non-existing MSRs) and a chance to detect bad faults
(note
>> that the kernel normal exception recovery mechanism may not be
usable
>> here because for example page faults first try to service the fault
>> before scanning the fixup tables, but a debugger will normally not
want
>> a page-in to happen behind its back). I thought the latter was what
gets
>> reported as DIE_OOPS, while the former would be the filtering
occasions
>> (and I actually took the "grossly misnamed" comment in asm/kdebug.h
as
>> additional indication for that).
>
>All you want is a hook early in GPF, right? I guess that should be
ok.
>I can see that it's useful on x86-64 due to the non canonical address

>fault resulting in GPFs mess. 

Yes. Now, would you see this to replace the current one, or in addition
to it?

Jan