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Date:   Tue, 16 May 2023 10:03:59 -0700
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Subject: Re: [PATCH v5 1/6] mm/gup: remove unused vmas parameter from
 get_user_pages()
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To:     David Hildenbrand <david@redhat.com>,
        Sean Christopherson <seanjc@google.com>
Cc:     Lorenzo Stoakes <lstoakes@gmail.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>, x86@kernel.org,
        linux-sgx@vger.kernel.org, amd-gfx@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, kvm@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        "H . Peter Anvin" <hpa@zytor.com>, Xinhui Pan <Xinhui.Pan@amd.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Dimitri Sivanich <dimitri.sivanich@hpe.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
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        Pavel Begunkov <asml.silence@gmail.com>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Christian Konig <christian.koenig@amd.com>,
        Jason Gunthorpe <jgg@nvidia.com>
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From:   John Hubbard <jhubbard@nvidia.com>
In-Reply-To: <7e9651d6-382a-287c-cd08-03762ccce1f7@redhat.com>
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On 5/16/23 07:35, David Hildenbrand wrote:
...
>>> When passing NULL as "pages" to get_user_pages(), __get_user_pages_locked()
>>> won't set FOLL_GET. As FOLL_PIN is also not set, we won't be messing with
>>> the mapcount of the page.
> 
> For completeness: s/mapcount/refcount/ :)

whew, you had me going there! Now it all adds up. :) 

thanks,
-- 
John Hubbard
NVIDIA