Re: [PATCH -v2 7/7] x86, NMI, Remove do_nmi_callback logic

Don Zickus
2010-09-30T04:04:48Z

On Wed, Sep 29, 2010 at 02:55:58PM +0800, huang ying wrote:
> Hi, Don,
>
> I think we all agree that to use order to determine the reason/source
> of NMI. The difference is that I want to keep as many direct calls in
> default_do_nmi() as possible, while you guys want to wrap almost all
> code in default_do_nmi() into notifier handler and leave only one
> notify_die() in defualt_do_nmi(). And I want to use different die_val
> (and their calling order in default_do_nmi()) to determine the order
> while you guys want to use priority (based on its value) to determine
> the order.

Well, I just wanted to see if we can minimize the number of times we
walked the die_chain. Priorities was an interesting idea, I am not sure
it works out. Registering two handlers, seems clunky. But I am open to
the discussions.

>
> On the other hand, I think we should call corresponding DIE_NMIxxx
> before the default operations, such as for watchdog, call
> DIE_NMIWATCHDOG before go panic, for unknown nmi, call DIE_NMIUNKNOWN
> before the default processing (may panic).
>
> I think it is important to distinguish between die chain used to
> determine the source/reason of NMI and the die chain used to see if
> any other driver wanted to do some processing before the default
> operation.

I guess I still prefer to take your patch set with its change and then
layer any new ideas on top. I have a feeling this discussion could go on
forever regarding how die_chains can work.

Cheers,
Don