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Date: Fri, 28 Apr 2017 08:33:23 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Thomas Garnier <thgarnie@google.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>,
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Subject: Re: [PATCH v8 1/4] syscalls: Verify address limit before returning
 to user-mode
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* Thomas Garnier <thgarnie@google.com> wrote:

> > BTW., a further simplification would be:
> >
> > #ifndef ADDR_LIMIT_CHECK_PRE
> > # define ADDR_LIMIT_CHECK_PRE ...
> > #endif
> >
> > This way architectures could override this generic functionality simply by
> > defining the helpers. Architectures that don't do that get the generic version.
> 
> I don't think architectures need to do that. The optimizations are
> embedding the checks on their architecture-specific code to make it
> faster and remove the size impact. The pre/post is fine for the rest.

Indeed, only the generic code needs to turn off that code - architectures will 
place these callbacks elsewhere.

Thanks,

	Ingo