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Subject: Re: [PATCH] x86/mm: disable preemption during CR3 read+write
To: Andy Lutomirski <luto@amacapital.net>
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        Mel Gorman <mgorman@suse.de>, Peter Zijlstra <a.p.zijlstra@chello.nl>
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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Date: Fri, 5 Aug 2016 17:52:38 +0200
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On 08/05/2016 05:42 PM, Andy Lutomirski wrote:
> 
> This should affect kernel threads too, right?

I don't think so because they don't have a MM in the first place so
they don't shouldn't need to flush a TLB. But then there is iounmap()
and vfree() for instance which does

vmap_debug_free_range()
{
   if (debug_pagealloc_enabled()) {
         vunmap_page_range(start, end);
         flush_tlb_kernel_range(start, end);
   }
}

so it looks like a candidate.

> Acked-by: Andy Lutomirski <luto@kernel.org>

Sebastian