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See http://www.infradead.org/rpr.html X-Stat-Signature: sujxq85x777hem6c5coogtz7rhyc1hfr X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 03FF420016 X-Rspam-User: X-HE-Tag: 1753342239-956017 X-HE-Meta: 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 17ZkFXDl IfcLUgZN/43+BDn5Df9Bql8jYSe9yqzm4wvElonCbUOiUGURZTgVAWsnXMhvO8HuDbFFFIn8/2q96Qm5AuZO2OhxL2k6Jxa/Zn8JL3Xh5dJTMIzQQ55rrP7GpYdyUbXjXP7gPmCXxsmXCN7CVO2qjIY9YHLd7hA9UzYMTyFyHKM52RY2DgvA+4+xn19160W4WPWVkn7u4Kg7rmCwZq5tIypNOTP4yxbvot3R4t3sHmwNYj1eYnC9ytbELH8CMHK8+v/aGBgsArsxkv8vuGnadmQCF4KghCn0lOSuWiUwlf1cV0/PXoLQ0uM7WZVF7dhldQDgXmYtGaj8XaZkuxuI1eT6zmV7L1KTlRbrRU0VScUXYmSdTcmR4PRXW+NEy6VDJmk9uWBOb6ogl0sgueRz4hScxTtA92ZbwBQt8QCMyXLYZpeRXIBILvou+rJaTA9+TALwQeySrH5a/u4k= 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 Wed, Jul 23, 2025 at 12:55:22AM -0300, Jason Gunthorpe wrote: > On Mon, Jul 21, 2025 at 12:03:41AM -0700, Christoph Hellwig wrote: > > On Fri, Jul 18, 2025 at 02:51:11PM +0300, Yonatan Maman wrote: > > > From: Yonatan Maman > > > > > > Add support for P2P for MLX5 NIC devices with automatic fallback to > > > standard DMA when P2P mapping fails. > > > > That's now how the P2P API works. You need to check the P2P availability > > higher up. > > How do you mean? > > This looks OKish to me, for ODP and HMM it has to check the P2P > availability on a page by page basis because every single page can be > a different origin device. > > There isn't really a higher up here... The DMA API expects the caller to already check for connectability, why can't HMM do that like everyone else?