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[47.55.120.4]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-4b3462ca49fsm11168561cf.31.2025.09.02.05.06.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Sep 2025 05:06:27 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1utPmM-00000000saf-2PL1; Tue, 02 Sep 2025 09:06:26 -0300 Date: Tue, 2 Sep 2025 09:06:26 -0300 From: Jason Gunthorpe To: Alistair Popple Cc: linux-mm@kvack.org, akpm@linux-foundation.org, david@redhat.com, osalvador@suse.de, jhubbard@nvidia.com, peterx@redhat.com, linux-kernel@vger.kernel.org, dan.j.williams@intel.com Subject: Re: [PATCH 1/2] mm/gup: Remove dead pgmap refcounting code Message-ID: <20250902120626.GA184112@ziepe.ca> References: <20250902051421.162498-1-apopple@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250902051421.162498-1-apopple@nvidia.com> On Tue, Sep 02, 2025 at 03:14:20PM +1000, Alistair Popple wrote: > Prior to aed877c2b425 ("device/dax: properly refcount device dax pages > when mapping") ZONE_DEVICE pages were not fully reference counted when > mapped into user page tables. Instead GUP would take a reference on the > associated pgmap to ensure the results of pfn_to_page() remained valid. > > This is no longer required and most of the code was removed by > fd2825b0760a ("mm/gup: remove pXX_devmap usage from get_user_pages()"). > Finish cleaning this up by removing the dead calls to put_dev_pagemap() > and the temporary context struct. > > Signed-off-by: Alistair Popple > --- > mm/gup.c | 67 ++++++++++++++++++++++---------------------------------- > 1 file changed, 26 insertions(+), 41 deletions(-) Reviewed-by: Jason Gunthorpe Yay! This never made alot of sense :\ Jason