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Date:   Wed, 14 Jun 2023 17:25:25 -0700
From:   Mike Kravetz <mike.kravetz@oracle.com>
To:     Peter Xu <peterx@redhat.com>
Cc:     David Hildenbrand <david@redhat.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Matthew Wilcox <willy@infradead.org>,
        Andrea Arcangeli <aarcange@redhat.com>,
        John Hubbard <jhubbard@nvidia.com>,
        Mike Rapoport <rppt@kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Andrew Morton <akpm@linux-foundation.org>,
        James Houghton <jthoughton@google.com>,
        Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH 4/7] mm/hugetlb: Prepare hugetlb_follow_page_mask() for
 FOLL_PIN
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On 06/14/23 11:51, Peter Xu wrote:
> On Wed, Jun 14, 2023 at 05:47:31PM +0200, David Hildenbrand wrote:
> > Right. Then just call patch #2 "Add missing write-permission check" and this
> > patch "Support FOLL_PIN in hugetlb_follow_page_mask()" or sth. like that.
> > 
> > Regarding the backport, I really wonder if patch #2 is required at all,
> > because I didn't sport any applicable FOLL_WRITE users. Maybe there were
> > some? Hm. If it's not applicable, a single "Support FOLL_PIN in
> > hugetlb_follow_page_mask()" patch might be cleanest.
> 
> Yeah, I agree.  The code is definitely needed, not the split of patches if
> no need for a backport.  Let me merge then.
> 

Should have read this before adding my RB to patch 2.  I assumed no
backport.  Agree, than merging the gup_must_unshare here makes more sense.
-- 
Mike Kravetz