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[73.158.218.242]) by smtp.gmail.com with UTF8SMTPSA id d9443c01a7336-23de434d5a7sm128947635ad.204.2025.07.16.14.54.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Jul 2025 14:54:13 -0700 (PDT) Date: Wed, 16 Jul 2025 14:54:12 -0700 From: Stanislav Fomichev To: Song Yoong Siang Cc: "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH bpf-next,v5 1/1] doc: xdp: clarify driver implementation for XDP Rx metadata Message-ID: References: <20250716154846.3513575-1-yoong.siang.song@intel.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250716154846.3513575-1-yoong.siang.song@intel.com> On 07/16, Song Yoong Siang wrote: > Clarify that drivers must remove device-reserved metadata from the > data_meta area before passing frames to XDP programs. > > Additionally, expand the explanation of how userspace and BPF programs > should coordinate the use of METADATA_SIZE, and add a detailed diagram > to illustrate pointer adjustments and metadata layout. > > Also describe the requirements and constraints enforced by > bpf_xdp_adjust_meta(). > > Signed-off-by: Song Yoong Siang > --- > V5: > - create a new section called 'Driver implementation' (Stanislav) > - reword 'utilize the data_meta area' to 'prepend metadata to received packets' (Jakub) Thanks! Acked-by: Stanislav Fomichev