[PATCH] ARM: fix "BUG: using smp_processor_id() in preemptible code"

Rabin Vincent rabin at rab.in
Mon Jan 4 09:50:27 EST 2010

On Fri, Jan 01, 2010 at 08:35:44PM +0000, Russell King - ARM Linux wrote:
> On Wed, Dec 30, 2009 at 10:47:20PM +0530, Rabin Vincent wrote:
> > Fix the following warning, which appears when the register dump for a
> > faulting process is printed in a kernel with SMP, DEBUG_PREEMPT, and
> > DEBUG_USER (with user_debug=31) enabled:
> Well, the CPU number displayed here in preemptible contexts is rather
> meaningless - it doesn't necessarily reflect the CPU where the problem
> originally occurred.
> Maybe we should use raw_smp_processor_id() here - which is fine because
> this is just debugging, and it being wrong doesn't cause unsafe
> conditions.

I agree, raw_smp_processor_id() makes more sense here than
{get/put}_cpu().  Revised patch below:


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