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[73.241.150.58]) by smtp.gmail.com with ESMTPSA id l83sm911928pfd.150.2020.06.17.17.14.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 17 Jun 2020 17:14:08 -0700 (PDT) Subject: Re: [PATCH net-next 1/5] net: tso: double TSO_HEADER_SIZE value To: Jakub Kicinski , Eric Dumazet Cc: "David S . Miller" , netdev , Eric Dumazet , Willem de Bruijn , Antoine Tenart References: <20200617184819.49986-1-edumazet@google.com> <20200617184819.49986-2-edumazet@google.com> <20200617170229.04454d36@kicinski-fedora-PC1C0HJN> From: Eric Dumazet Message-ID: <1b5a59d6-ef9c-81e0-9a78-f0eedfc3a40b@gmail.com> Date: Wed, 17 Jun 2020 17:14:06 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200617170229.04454d36@kicinski-fedora-PC1C0HJN> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 6/17/20 5:02 PM, Jakub Kicinski wrote: > On Wed, 17 Jun 2020 11:48:15 -0700 Eric Dumazet wrote: >> Transport header size could be 60 bytes, and network header >> size can also be 60 bytes. Add the Ethernet header and we >> are above 128 bytes. >> >> Since drivers using net/core/tso.c usually allocates >> one DMA coherent piece of memory per TX queue, this patch >> might cause issues if a driver was using too many slots. >> >> For 1024 slots, we would need 256 KB of physically >> contiguous memory instead of 128 KB. >> >> Alternative fix would be to add checks in the fast path, >> but this involves more work in all drivers using net/core/tso.c. >> >> Fixes: f9cbe9a556af ("net: define the TSO header size in net/tso.h") >> Signed-off-by: Eric Dumazet >> Cc: Antoine Tenart > > Some warnings popping up in this series with W=1 C=1: > > drivers/net/ethernet/marvell/octeontx2/af/common.h:65:26: warning: cast truncates bits from constant value (100 becomes 0) > Nice, thanks I will take a look.