Re: What's up with the IP stack?

On Sunday 12 October 2003 11:03 am, Andre Guibert de Bruet wrote:
> On Sun, 12 Oct 2003, Josef Karthauser wrote:
> > On Sun, Oct 12, 2003 at 02:48:01PM +0200, Soren Schmidt wrote:
> > > It seems Josef Karthauser wrote:
> > > > I've just built and installed a new kernel, the first since Aug 6th.
> > > > There appears to be a problem with the IP stack.  What happens is
> > > > that everything is fine for a few hours, and then the IP stack stops
> > > > working. I can no longer ping anything on the local network, my
> > > > default route drops out (which is probably dhclient's doing). 
> > > > Perhaps it is ARP that is broken, it's hard to tell.  All I know is
> > > > that I need to reboot to make it work again.
> > > >
> > > > Is anyone else experiencing this kind of problem?
> > >
> > > Do you have dummynet included in the kernel ?
> > > That has been broken for me since sam's latest commit as a backout
> > > of ip_dummynet.c fixes the problem for me...
> >
> > No, I've not got dummynet in there.  My current kernel config is:
>
> I experienced this a week ago. I found that ifconfig'ing the interface
> down and back up again "fixed" the problem. I've since reverted to a
> kernel compiled on September 25th.

It would be good to know more details; I still don't have much to go on.  Try 
to identify, for example, if the problem is specific to a particular 
device/interface or feature you're using (e.g dummynet).  If you have ddb in 
your system, then when the system gets into a bad state break into the 
debugger and look for threads that are blocked on locks.  If you have witness 
in your kernel then show locks would also be useful.  If you don't have 
witness in your system then rebuild your kernel with it.

The most recent round of changes were to lock the routing table.  These went 
in 10/3 and were extensive. They could easily be the problem but w/o more 
info I can't really help.

	Sam