Re: [PATCH 0/5] Generic smp_call_function(), improvements, and smp_call_function_single()

[Jens Axboe <jens.axboe@oracle.com>]

On Fri, Mar 21 2008, Luck, Tony wrote:
> > When/if more archs are converted, it'll of course look even better.
> > Comments? I've verified that this builts and boots on x86, x86-64
> > and powerpc. IA64 may still need a one-liner change, I don't have
> > access to that platform anymore so I can't verify that myself. It
> > does build, however :-)
> 
> Can you give me a clue as to which line needs the one-liner ... although
> it builds cleanly for IA64 it panics with a dereference NULL fault. It

My thinking was that it may need a bit of help to ensure that the init
function for single call data works,
kernel/smp.c:init_call_single_data() specifically. It may be run before
the arch code has setup all CPU related structures, not sure...

> looks like we were in the list_add_tail(&data->list, &dst->list) code.

Is it data or dst being NULL? Looking at your trace, it must be dst.
Which makes me believe that it is indeed a missing call of the above
function at the right time. So some help would be accepted there :)

-- 
Jens Axboe