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Date: Thu, 27 Oct 2016 12:59:04 +0200
From: Michal Hocko <mhocko@kernel.org>
To: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: linux-mm@kvack.org, Linus Torvalds <torvalds@linux-foundation.org>,
        Jan Kara <jack@suse.cz>, Hugh Dickins <hughd@google.com>,
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Subject: Re: [PATCH 1/2] mm: add locked parameter to get_user_pages_remote()
Message-ID: <20161027105903.GI6454@dhcp22.suse.cz>
References: <20161027095141.2569-1-lstoakes@gmail.com>
 <20161027095141.2569-2-lstoakes@gmail.com>
 <20161027105527.GG6454@dhcp22.suse.cz>
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On Thu 27-10-16 12:55:27, Michal Hocko wrote:
> On Thu 27-10-16 10:51:40, Lorenzo Stoakes wrote:
> > This patch adds a int *locked parameter to get_user_pages_remote() to allow
> > VM_FAULT_RETRY faulting behaviour similar to get_user_pages_[un]locked().
> > 
> > Taking into account the previous adjustments to get_user_pages*() functions
> > allowing for the passing of gup_flags, we are now in a position where
> > __get_user_pages_unlocked() need only be exported for his ability to allow
> > VM_FAULT_RETRY behaviour, this adjustment allows us to subsequently unexport
> > __get_user_pages_unlocked() as well as allowing for future flexibility in the
> > use of get_user_pages_remote().
> 
> I would also add that this shouldn't introduce any functional change.

Forgot to mention that this also opens doors to change other g_u_p_r
callers to allow FAULT_RETRY logic.

-- 
Michal Hocko
SUSE Labs