9.0-RC1 panic in tcp_input: negative winow.

[Garrett Cooper]

On Sun, 23 Oct 2011, Lawrence Stewart wrote:

> On 10/22/11 19:49, Pawel Jakub Dawidek wrote:
>> The panic message says:
>>
>> 	panic: tcp_input negative window: tp 0xfffffe007763e000 rcv_nxt 
>> 3718269252 rcv_adv 3718268291
>> 
>> I only have picture of the backtrace:
>>
>> 	http://people.freebsd.org/~pjd/misc/panic_negative_window.jpg
>> 
>
> ewww that is not good. Can you give us any more information about the machine 
> and what it's doing? Is it terminating TCP connections from the internet at 
> large or only local LAN (i.e. is there likely to be packet loss happening)? 
> Are you doing TSO or LRO? Do you have any non-default tuning in place?

I can't speak for pjd@, but when this issue occured a couple months ago 
for me, the system I had run into the issue with was doing packet 
forwarding via ipfw from an internal NAT via ipfw to a corporate network.

The system was using bce(4) on the internal and external interface.

Thanks,
-Garrett