From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794770585; b=zrUzRypfvmdtHrav6aDuDIW54JywgYhbBmI6JiIsKrLz0oUuGnVlPCzhstguM1F4tiPK 8jjgOtuY1BHx35zBE4GB/PwCSzei/hwKbR0wcKskz+jItAIaH6idUmVTIIejoDjxGxH0N dL7EHeLUzNK/pNfD9UyP+YQpiZEC16EaNuAWEbQ3RfZIO78vw0gwyYOOSDNu5a6p30f46 3baCVScOWB/DSj0jnnHiqfEYLgRlzChuUzzepU3Qw7Dvc/C67ZN0uTuoJIBSxstCWiQHG qlpL5WR+Ulsl2lxW2cZVU4p4OKq2Q3e55huz2p5QycfBnxt7ENHDomCftrv8vwInC7Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794770585; h=Received:DKIM-Signature:From:To:Cc:Subject:In-Reply-To:References: Date:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding; bh=lQOjQXnCDqOZeDgjlwwko2gcjA/gK2MjwIx70kisX54=; b=WMggsiUGjM3N3nlFC5pnzAiG8qemjshz9sGKIWX8fLXyEQv+e/Luj0Zfb3rhF4ZdJqEz KqfI3btj/DeY2n0QLu7vbkINnxcrl3eePRIftnllRZpG7PkneKDnw/6cF8g8BhLpW2ECV hDQG8HuBuY/UAd1Z3IuMlDFFPu42tJ8CeeOK04zVAByU5axmpYMax+IRWTaTowb6J/gbT jAXpolD/k56YnGs+GtOgcXEWEiB4tGb/QlIsHtto0UygES6zWKe6XGBRqe36Bkusb+JZZ Wo0BSG0h9RJuH/wVNmruv4ARq1XJhAXtDenpLKoVQ9BjvPfsIKayBJ69HsAOSfgLo8A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=M66ScdV5; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D7022606A335; Sun, 15 Nov 2026 19:23:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=M66ScdV5 Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1EE61F000C5; Sun, 15 Nov 2026 19:23:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794770585; bh=lQOjQXnCDqOZeDgjlwwko2gcjA/gK2MjwIx70kisX54=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=M66ScdV5h+nAP8WBXt+vpiUvnmD94r+c2ZaVEMETbDJ4Z1nCaYUFDFoYi9XdgeIv/ Cz4fFZuwg1v360MvRoNa+R0BsRK1G55P2hApxkQb1IEMfFzqYn9rk5aDif3WbhCKJO +OfPAuBMVIYMe7CMt3hFcdiwM2CkLxLATCYwvI7Zdkdi7jDYjAssa3rphmVw7HxmnY SEUqKdoC9sZXTyDqoylZZB6qmTCdd4o27PYraZ7BVAd4cyqPfLlk97bl4ewhJJ5Wsc KrcFnscQY8HLr6b2ZJaOaKjL0Ny0zfnqZNv1pfcmABvkQnDoXO3yD1X3KVSSJMFkWd z6lvela8xepMQ== From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= To: netdev-bot+sashiko@kernel.org Cc: magnus.karlsson@intel.com, maciej.fijalkowski@intel.com, sdf@fomichev.me, davem@davemloft.net, edumazet@kernel.org, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, corbet@lwn.net, skhan@linuxfoundation.org, rdunlap@infradead.org, alexanderduyck@fb.com, kernel-team@meta.com, andrew+netdev@lunn.ch, hawk@kernel.org, ilias.apalodimas@linaro.org, ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, asml.silence@gmail.com, axboe@kernel.dk, andrii@kernel.org, eddyz87@gmail.com, memxor@gmail.com, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, jolsa@kernel.org, emil@etsalapatis.com, ihor.solodrai@linux.dev, netdev@vger.kernel.org, bpf@vger.kernel.org, io-uring@vger.kernel.org, almasrymina@google.com, mike.marciniszyn@gmail.com, bestswngs@gmail.com, razor@blackwall.org, dw@davidwei.uk, aleksander.lobakin@intel.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, stuclar@meta.com Subject: Re: [PATCH net-next v1 07/11] xsk: Deliver provider chunks without copying In-Reply-To: <179443689590.2199510.9741809616593174859@kernel.org> References: <20261110102039.1002605-8-bjorn@kernel.org> <179443689590.2199510.9741809616593174859@kernel.org> Date: Sun, 15 Nov 2026 20:23:02 +0100 Message-ID: <87fqx1hpbd.fsf@all.your.base.are.belong.to.us> X-Mailing-List: netdev@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable netdev-bot+sashiko@kernel.org writes: > Should this be gated by a flag? Or should the commit message describe it > as a UAPI change rather than as a device property? Neither, it isn't a UAPI change. The headroom text predates multi-buffer, when a buffer held a whole packet: "the packet will start N bytes into the buffer". A continuation buffer doesn't start a packet, and the room in front of the packet, for headers or metadata, is still there in its first buffer. Userspace reads each buffer at the address in its descriptor anyway; XDP can already move the start with bpf_xdp_adjust_head(). The doc change only spells out a valid multi-buffer variant, and I'll say so in the commit message. I'll also fix the commit message on the old copy path, and give net_mp_release_page_pool_bulk() its own page_pool patch. Bj=C3=B6rn