David Greenman wrote: >>I am playing with a driver for the Broadcom 5700/5701. >> >>It recognizes the 5700 in my 3Com cards OK, but seems to screw up the >>TCP checksum. >> >>Switching off hardware checksum capability fixes it. >> >>Does anyone know the details of which stepping this stuff worked on? >> > > I haven't nailed down the problem that I've seen with them to a specific >chipset, but I can confirm that they incorrectly calculate the checksum on >input packets in some cases. It seems to be related to both packet size and >certain TCP options (or lack of them). I've only seen the problem occur with >very small (0-4 byte payload) packets. > In any case, after discussing this problem with Bill Paul, I disabled >input checksum in the -current driver and intend to merge that to -stable in >a few days. > OK, that makes sense, because I wasn't getting past first base. SYN ACK segments werre being rejected with bad checksum.
The driver I modified is actually for the 5701, which works fine with all checksum offloading enabled. I will try to disable just receive TCP checksum and see what happens. -- Richard Sharpe, [EMAIL PROTECTED], LPIC-1 www.samba.org, www.ethereal.com, SAMS Teach Yourself Samba in 24 Hours, Special Edition, Using Samba To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
