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Date: Fri, 15 Dec 2017 08:51:47 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>,
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Subject: Re: [PATCH v2 01/17] mm/gup: Fixup p*_access_permitted()
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On Thu, Dec 14, 2017 at 10:09:24PM -0800, Linus Torvalds wrote:
> On Dec 14, 2017 21:04, "Dave Hansen" <dave.hansen@intel.com> wrote:
> Can we please just undo that broken crap instead of trying to "fix" it?
> 
> It was wrong. We absolutely do not want to complicate the gup path.
> 
> Let's fet rid of those broken p??_access_permited() things.

So we actually need the pte_access_permitted() stuff if we want to
ensure we're not stepping on !PAGE_USER things.