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Date:   Thu, 6 Apr 2023 15:29:28 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Marcelo Tosatti <mtosatti@redhat.com>
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Subject: Re: [PATCH 3/3] mm/mmu_gather: send tlb_remove_table_smp_sync IPI
 only to CPUs in kernel mode
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References: <20230404134224.137038-1-ypodemsk@redhat.com>
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On Thu, Apr 06, 2023 at 09:38:50AM -0300, Marcelo Tosatti wrote:

> > To actually hit this path you're doing something really dodgy.
> 
> Apparently khugepaged is using the same infrastructure:
> 
> $ grep tlb_remove_table khugepaged.c 
> 	tlb_remove_table_sync_one();
> 	tlb_remove_table_sync_one();
> 
> So just enabling khugepaged will hit that path.

Urgh, WTF..

Let me go read that stuff :/