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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Guillaume Autran <gautran@mrv.com>
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Subject: Re: [PATCH] 8xx: get_mmu_context() for (very) FEW_CONTEXTS
	and	KERNEL_PREEMPT race/starvation issue
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> I'm still a bit confused with "kernel preemption". One thing for sure
> is that disabling kernel preemption does indeed fix my problem.
> So, my question is, what if a task in the middle of being schedule
> gets preempted by an IRQ handler, where will this task restart
> execution ? Back at the beginning of schedule or where it left of ?

I very much doubt that schedule itself can be preempted :)

> The idea behind my patch was to get rid of that nr_free_contexts
> counter that is (I thing) redundant with the context_map.