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Subject: Re: percpu related boot crash on x86
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Pekka Enberg <penberg@kernel.org>
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Date: Thu, 20 Jan 2011 11:47:47 +0100
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On Thu, 2011-01-20 at 10:31 +0200, Pekka Enberg wrote:
>    if (!irqs_disabled())
> 
> guard around the debugging code to make vfree() always work with IRQs 
> disabled. 

That won't be sufficient, __purge_vmap_area_lazy() needs to call
flush_tlb_kernel_range() occasionally.

There really is a good reason vmalloc()/vfree() don't work with
interrupts disabled.