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

From: Mark Rutland
Date: Tue Apr 16 2019 - 10:42:08 EST


On Tue, Apr 16, 2019 at 04:31:27PM +0200, Laurent Dufour wrote:
> Le 16/04/2019 Ã 16:27, Mark Rutland a ÃcritÂ:
> > On Tue, Apr 16, 2019 at 03:44:55PM +0200, Laurent Dufour wrote:
> > > From: Mahendran Ganesh <opensource.ganesh@xxxxxxxxx>
> > >
> > > Set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT for arm64. This
> > > enables Speculative Page Fault handler.
> > >
> > > Signed-off-by: Ganesh Mahendran <opensource.ganesh@xxxxxxxxx>
> >
> > 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.