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Date: Fri, 11 Sep 2020 09:09:39 +0200
From: peterz@infradead.org
To: Jason Gunthorpe <jgg@ziepe.ca>
Subject: Re: [RFC PATCH v2 1/3] mm/gup: fix gup_fast with dynamic page table
 folding
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On Thu, Sep 10, 2020 at 06:59:21PM -0300, Jason Gunthorpe wrote:
> So, I suggest pXX_offset_unlocked()

Urgh, no. Elsewhere in gup _unlocked() means it will take the lock
itself (get_user_pages_unlocked()) -- although often it seems to mean
the lock is already held (git grep _unlocked and marvel).

What we want is _lockless().