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Tue, 03 Nov 2026 14:43:39 -0800 (PST) Received: from localhost ([2a03:2880:9ff:6a::]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-36ca3966daasm1484975eec.23.2026.11.03.14.43.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Nov 2026 14:43:39 -0800 (PST) Date: Tue, 3 Nov 2026 14:43:31 -0800 From: Stanislav Fomichev To: Mina Almasry Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jakub Kicinski , Willem de Bruijn , Eric Dumazet , Kaiyuan Zhang , io-uring@vger.kernel.org, Stanislav Fomichev , Paolo Abeni , "David S. Miller" , Simon Horman , Pavel Begunkov , Jens Axboe , Bobby Eshleman , Daniel Borkmann , Neal Cardwell , Kuniyuki Iwashima , David Ahern , Ido Schimmel Subject: Re: [PATCH net-next v2 3/4] net: add skb_frags_can_coalesce() helper Message-ID: References: <20261102231827.4088254-1-almasrymina@google.com> <20261102231827.4088254-4-almasrymina@google.com> X-Mailing-List: linux-kernel@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-Disposition: inline In-Reply-To: <20261102231827.4088254-4-almasrymina@google.com> On 11/02, Mina Almasry wrote: > Add skb_has_net_iovs(skb), assuming skb->unreadable and net_iov-backed > frags are equivalent for now (with a comment noting the two can be > decoupled in the future if readable net_iovs are introduced). > > Also add skb_mem_provider_compat() and skb_frags_can_coalesce() so all > multi-skb coalescing, shifting, and GRO paths can share a single check > across pp_recycle, skb_zcopy(), and fragment memory providers: > - empty 0-length skbs are compatible without mixing readable payload > - page vs net_iov is rejected via skb_has_net_iovs() (0 pointer chases) > - page vs page is allowed via !skb_has_net_iovs() (0 pointer chases) > - net_iov vs net_iov compares mp_priv (walking frag_list if nr_frags is 0) Maybe squash this and patch #4? Otherwise hard to follow :-(