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Date: Thu, 20 Oct 2016 21:26:47 +0200
From: Michal Hocko <mhocko@kernel.org>
To: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>, linux-mm@kvack.org,
 Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly
 pass FOLL_* flags
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On Wed 19-10-16 10:23:55, Dave Hansen wrote:
> On 10/19/2016 10:01 AM, Michal Hocko wrote:
> > The question I had earlier was whether this has to be an explicit FOLL
> > flag used by g-u-p users or we can just use it internally when mm !=
> > current->mm
> 
> The reason I chose not to do that was that deferred work gets run under
> a basically random 'current'.  If we just use 'mm != current->mm', then
> the deferred work will sometimes have pkeys enforced and sometimes not,
> basically randomly.

OK, I see (async_pf_execute and ksm ). It makes more sense to me. Thanks
for the clarification.

-- 
Michal Hocko
SUSE Labs