Interesting TCP issue

[Andre Oppermann]

Julian Elischer wrote:
> Steve Watt wrote:
>> On Jan 22,  9:15, Uwe Doering wrote:
>> } Subject: Re: Interesting TCP issue
>> } Steve Watt wrote:
>> } > In <459AD141.5010502 at elischer.org>, Julian Elischer wrote:
>> } > } > [ Snip discussion of symptoms of window scaling broken when
>> } > talking to at least the skype mail servers. ]
>> } > } >> we have seen this since 4.x
>> } >> I think a fix may be in 7.0 but I'm not sure..
>> } >> I thin kthere is a problem when the far end sets the window down 
>> to 1 } >> but scales it by a factor of 2^{big number}.
>> } >>
>> } >> Andre, can you check out this problem and MFC the correct fix
>> } >> if it is indeed the same problem in 6.2?
>> } > } > It is the same problem; I took the (one-line) fix as indicated by
>> } > } >> 
>> http://cvs.ironport.com/cgi-bin/viewcvs.cgi/freebsd/src/sys/netinet/tcp_syncache.c.diff?r1=1.84&r2=1.85 
>>
>> } > } > (well, not cvs.ironport.com, which doesn't seem to exist at 
>> the moment),
>> } > and applied the diff from 1.84 to
>> } > 1.85 and to a 6.2-PRERELEASE box updated around 25 Dec 06.
>> } > It works like a charm.
>> } > } > I would vote to MFC 1.85 now that 6.2 is out.
>> } } I wonder whether it is that easy.  As far as I can tell the commit 
>> to } HEAD actually comprised changes to three files:
>>
>> I wonder as well, but that single diff fixes the problem I was running
>> into with the skype mail servers.
>>
>> } 
>> http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/tcp_input.c.diff?r1=1.290&r2=1.291 
>>
>> } 
>> http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/tcp_syncache.c.diff?r1=1.84&r2=1.85 
>>
>> } 
>> http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/tcp_var.h.diff?r1=1.127&r2=1.128 
>>
>> } } How about the modifications in 'tcp_input.c'?  Are they relevant 
>> to the } problem this thread is about?  If so, assessing the 
>> correctness of an } MFC might prove to be a little harder.
> 
> 
> 
> That's why I asked Andre to look at it but he's not responding..

He's about to re-appear @freebsd.

-- 
Andre