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Date:   Sun, 25 Mar 2018 14:50:03 -0700 (PDT)
From:   David Rientjes <rientjes@google.com>
To:     Laurent Dufour <ldufour@linux.vnet.ibm.com>
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Subject: Re: [PATCH v9 01/24] mm: Introduce CONFIG_SPECULATIVE_PAGE_FAULT
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On Tue, 13 Mar 2018, Laurent Dufour wrote:

> This configuration variable will be used to build the code needed to
> handle speculative page fault.
> 
> By default it is turned off, and activated depending on architecture
> support.
> 
> Suggested-by: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
> ---
>  mm/Kconfig | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/mm/Kconfig b/mm/Kconfig
> index abefa573bcd8..07c566c88faf 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -759,3 +759,6 @@ config GUP_BENCHMARK
>  	  performance of get_user_pages_fast().
>  
>  	  See tools/testing/selftests/vm/gup_benchmark.c
> +
> +config SPECULATIVE_PAGE_FAULT
> +       bool

Should this be configurable even if the arch supports it?