Zwane Mwaikambo <[EMAIL PROTECTED]> wrote:
>
> On Wed, 13 Apr 2005, Luck, Tony wrote:
> 
> > But my local cpu hotplug expert (Ashok) has this to say about
> > the irq redirection part of the i386 code:
> > 
> > On i386, the way they do in fixup_irqs() to 
> > 
> >   Redirect interrupts
> >   Local_irq_enable() // hack to permit irq processing
> >   Mdelay();; hack to wait
> >   Local_irq_disable()
> > 
> > Is totally not the right solution, there are easy cases that a race
> > condition can be triggered, and chipsets can also lockup if you do
> > programming the rte's without disabling them first.
> > 
> > This really ought to be fixed before putting it into production
> > kernels.
> > 
> > They also need to change irq to deferred mode when we do proc/irq
> > write handling like what we do for ia64.
> 
> I'd prefer doing that change as a followup, but i'm fine with doing it 
> before, i'm  just trying to avoid patches dependent on this backing up.

That sounds reasonable at this stage, if the racy code is only used during
"hotplugging".  But I don't think that's the case, is it?

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