Ubuntu
linux-source-2.6.20 package

skge driver causes TCP download failure

Bug #121423 reported by Markus Lindström
2
Affects Status Importance Assigned to Milestone
linux (Ubuntu)
Incomplete
Undecided
Unassigned
linux-source-2.6.20 (Ubuntu)
Won't Fix
Undecided
Unassigned

Bug Description

Binary package hint: linux-image-2.6.20-16-generic

It seems I've uncovered a major bug in the skge driver, which is used by my Marvell Technology Group Ltd. 88E8001 Gigabit Ethernet Controller (rev 13) network interface card.

The bug is easily shown with the following console command:
$ curl http://www.scmbb.ulb.ac.be/Users/jvanheld/biologie_societe/home.html

The download of that page suddenly halts at exactly the same point every single time. I've been unable to reproduce the bug on Windows on the same PC, as well as on my other Ubuntu 7.04 box which uses the same kernel, but uses the Atheros driver. I've thus come to the conclusion that skge is the culprit here.

I unfortunately can't give any more information than this at the present time ; nothing shows up neither syslog or dmesg about any kind of problem.

Revision history for this message
Markus Lindström (mlindstr) wrote :

Here are the usual files that are usually requested: lspci, dmesg and lshal.

Revision history for this message
Markus Lindström (mlindstr) wrote :

I just tried putting the HTML file on my own server and downloading it from there; that worked. Thus, it seems the server I'm downloading from plays a role as well.

Revision history for this message
Markus Lindström (mlindstr) wrote :

Here's also a Wireshark dump which shows what happens when I attempt to download said file. The transfer simply hangs in this state; after four minutes, still nothing more than this had happened.

Revision history for this message
jcfp (jcfp) wrote :

These symptoms are caused by tcp window scaling problems (on the www.scmbb.ulb.ac.be server, not on your ubuntu system); see bug #59331 and bug #89160 for more details. Please try disabling tcp window scaling as per the instructions found in these bug reports to fix this problem.

Changed in linux-source-2.6.20:
status: Unconfirmed → Needs Info
Revision history for this message
Markus Lindström (mlindstr) wrote :

Disabling TCP windows scaling indeed did the trick. I would recommend disabling this by default since it seems to cause these kinds of obscure bugs with various configurations. Even if it's not Ubuntu's fault, we can't fix every server out there, or hope they ever will get fixed anyway.

Thanks for your help!

jcfp (jcfp)
Changed in linux-source-2.6.20:
status: Incomplete → New
Revision history for this message
Markus Lindström (mlindstr) wrote :

I've still got one question, though. If TCP window scaling causes issues because of a broken router in front of the target server, then why can I access the resource from another Ubuntu 7.04 system with scaling enabled?

Revision history for this message
Launchpad Janitor (janitor) wrote : This bug is now reported against the 'linux' package

Beginning with the Hardy Heron 8.04 development cycle, all open Ubuntu kernel bugs need to be reported against the "linux" kernel package. We are automatically migrating this bug to the new "linux" package. However, development has already began for the upcoming Intrepid Ibex 8.10 release. It would be helpful if you could test the upcoming release and verify if this is still an issue - http://www.ubuntu.com/testing . If the issue still exists, please update this report by changing the Status of the "linux" task from "Incomplete" to "New". We appreciate your patience and understanding as we make this transition. Thanks!

To post a comment you must log in.
This report contains Public information  
Everyone can see this information.
Subscribing...

Other bug subscribers

Remote bug watches

Bug watches keep track of this bug in other bug trackers.