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charset=us-ascii Content-Disposition: inline In-Reply-To: <20241108150226.GM35848@ziepe.ca> User-Agent: Mutt/1.5.17 (2007-11-01) X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: D6060120012 X-Stat-Signature: r75me5qfqqf4q4tokxut3xjhsi8r6tux X-HE-Tag: 1731078257-279466 X-HE-Meta: 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 tR2fkpcY Nr8dFSt4cs8CKUUz8NpaeAs9L/S5Q12FuN5czndYKPMnXEwe8x2nfHNJJkKghrJB0xnYPuYHOWC6j4oY= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Nov 08, 2024 at 11:02:26AM -0400, Jason Gunthorpe wrote: > It is fully OK? Can't dma_map_page() trigger swiotlb? It must not do > that for P2P. How does it know the difference if it just gets a phys? dma_direct_map_page checks for p2p pages in the swiotlb bounce path already in the current kernel, and dma_map_sg relies on exactly that check to prevent bouncing for p2p.