[PATCH v12 04/31] arm64/mm: define ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT

[Laurent Dufour]

Le 16/04/2019 à 16:27, Mark Rutland a écrit :
> On Tue, Apr 16, 2019 at 03:44:55PM +0200, Laurent Dufour wrote:
>> From: Mahendran Ganesh <opensource.ganesh at gmail.com>
>>
>> Set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT for arm64. This
>> enables Speculative Page Fault handler.
>>
>> Signed-off-by: Ganesh Mahendran <opensource.ganesh at gmail.com>
> 
> This is missing your S-o-B.

You're right, I missed that...

> 
> The first patch noted that the ARCH_SUPPORTS_* option was there because
> the arch code had to make an explicit call to try to handle the fault
> speculatively, but that isn't addeed until patch 30.
> 
> Why is this separate from that code?

Andrew was recommended this a long time ago for bisection purpose. This 
allows to build the code with CONFIG_SPECULATIVE_PAGE_FAULT before the 
code that trigger the spf handler is added to the per architecture's code.

Thanks,
Laurent.

> Thanks,
> Mark.
> 
>> ---
>>   arch/arm64/Kconfig | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 870ef86a64ed..8e86934d598b 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -174,6 +174,7 @@ config ARM64
>>   	select SWIOTLB
>>   	select SYSCTL_EXCEPTION_TRACE
>>   	select THREAD_INFO_IN_TASK
>> +	select ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT
>>   	help
>>   	  ARM 64-bit (AArch64) Linux support.
>>   
>> -- 
>> 2.21.0
>>
>