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Date:   Tue, 16 Apr 2019 15:41:56 +0100
From:   Mark Rutland <mark.rutland@arm.com>
To:     Laurent Dufour <ldufour@linux.ibm.com>
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Subject: Re: [PATCH v12 04/31] arm64/mm: define
 ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT
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On Tue, Apr 16, 2019 at 04:31:27PM +0200, Laurent Dufour wrote:
> 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@gmail.com>
> > > 
> > > Set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT for arm64. This
> > > enables Speculative Page Fault handler.
> > > 
> > > Signed-off-by: Ganesh Mahendran <opensource.ganesh@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.

Ok. I think it would be worth noting that in the commit message, to
avoid anyone else asking the same question. :)

Thanks,
Mark.