On Wed, Dec 14, 2011 at 10:17:41PM +0100, Andrea Venturoli wrote: > On 12/14/11 20:59, YongHyeon PYUN wrote: > > >AFAIK the firmware of controller has no known TSO issue so it > >indicates a bug in driver. > >What makes me wonder is ICMP ECHO packet should not be affected by > >TSO and I have no clue at this moment. > > I wasn't talking about ICMP ECHO. > > What happened was: > a) the client connected to my server, advertising a TCP MSS of X; > b) my server started sending with packets larger than X (possibly it > misinterpreted MSS size???); > c) an ICMP packet arrived, asking my server to send packets no larger > than Y (I guess it was ignored); > d) my server kept resending the same (too big) packets; > e) it eventually reduced packet size, but it was still larger than Y; > ... > > Wireshark showed some wrong checksums (I believe on the ICMP packet, but > I might remember wrong).
You can check whether you received bad checksummed frames with netstat(1). > Of course this made a bell ring and removing TSO solved everything. > > > > >(Here, I assume you've > >captured packets on receiver side since bpf sees packets before > >hardware computes checksum.) > > Yes, although I don't have them anymore. > > > > >If you have a reliable way that reproduces the issue, let me know. > > I can turn TSO on again, save the packets and send them to you. > I just hope nothing changes on the Internet in between the server and > the client. > Let me know if you need/want this and I'll arrange in the next few days. > Let me know MSS of both client and server. Is simple downloading from client to server is enough to trigger the issue? Packet capture that shows the problem would be great to know what's going on here. > > > bye & Thanks > av. _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
