TCP differences in 7.2 vs 7.1

[Lars Eggert]

Hi,

On 2009-5-14, at 11:27, Pyun YongHyeon wrote:
> Then you're seeing different problem on em(4). Last time I checked
> em(4) TSO code in em(4) didn't use m_pullup and just returned
> ENXIO to caller. I'm not sure that is related with your issue but
> would you tell us your network configuration?

this box is a Dell 2950 server/router running 7.2-STABLE. It has an  
onboard bce interface and four dual-port Intel PRO/1000 NICs, giving  
it 8 em interfaces. (Let me know if you want the boot dmesg.)

> If you can easily
> reproduce the issue would you let us know?

Reproducing the issue is as easy as setting net.inet.tcp.tso=1.

What's interesting is that I only see the issue on one of the eight em  
interfaces. That interface is connected to a D-Link DIR-655 WLAN  
router. When I tcpdump on the other interfaces with TSO enabled, I see  
no "IP bad-len 0" messages.

Lars