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<div>Hi All:</div>
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<div>I want to build TOE(tcp checksum offload engine) in our hardware to improve the overall performance of NIC, however, i met a problem as follow:</div>
<div>AS you know, <font face="Arial, sans-serif" size="2">t</font><font face="Arial, sans-serif" size="2">he</font><font face="Arial, sans-serif" size="2"> TCP</font><font face="Arial, sans-serif" size="2"> checksum protect the TCP pseudo header+TCP header+Data</font><font face="Arial, sans-serif" size="2">,
if</font><font face="Arial, sans-serif" size="2"> TCP</font><font face="Arial, sans-serif" size="2"> packet is fragmented into many fragments, </font><font face="Arial, sans-serif" size="2">the hardware will have not enough information to generate tcp checksum
for the whole TCP</font><font face="Arial, sans-serif" size="2"> </font><font face="Arial, sans-serif" size="2">PDU</font><font face="Arial, sans-serif" size="2">, how to overcome this problem?</font></div>
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<div><font face="Arial, sans-serif" size="2">I searched in NIC driver source code of different vendor, found that TOE is generally used, I wonder whether the kernel will calculate the TCP checksum even we set features of this device as NETIF_F_IP_CSUM when
fragmentation happens.</font></div>
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<div><font face="Arial, sans-serif" size="2">Can anyone throw some lights on this problem?</font></div>
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<div><font face="Arial, sans-serif" size="2">Thanks a lot.</font></div>
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<div><font face="Arial, sans-serif" size="2">Rick.</font></div>
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