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[73.158.218.242]) by smtp.gmail.com with UTF8SMTPSA id d2e1a72fcca58-78102b23092sm2580058b3a.60.2025.09.25.11.28.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Sep 2025 11:28:56 -0700 (PDT) Date: Thu, 25 Sep 2025 11:28:56 -0700 From: Stanislav Fomichev To: Maciej Fijalkowski Cc: bpf@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, netdev@vger.kernel.org, magnus.karlsson@intel.com, kerneljasonxing@gmail.com Subject: Re: [PATCH v2 bpf-next 2/3] xsk: remove @first_frag from xsk_build_skb() Message-ID: References: <20250925160009.2474816-1-maciej.fijalkowski@intel.com> <20250925160009.2474816-3-maciej.fijalkowski@intel.com> Precedence: bulk X-Mailing-List: bpf@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: <20250925160009.2474816-3-maciej.fijalkowski@intel.com> On 09/25, Maciej Fijalkowski wrote: > Instead of using auxiliary boolean that tracks if we are at first frag > when gathering all elements of skb, same functionality can be achieved > with checking if skb_shared_info::nr_frags is 0. > > Remove @first_frag but be careful around xsk_build_skb_zerocopy() and > NULL the skb pointer when it failed so that common error path does not > incorrectly interpret it during decision whether to call kfree_skb(). > > Signed-off-by: Maciej Fijalkowski Acked-by: Stanislav Fomichev