panic: Duplicate free of item 0xffffff005c4a8600 from zone 0xffffff007fed4780(Mbuf)

[Robert Watson]

On Sun, 18 Jul 2004, Bruce M Simpson wrote:

> On Sun, Jul 18, 2004 at 03:59:02PM +0200, Willem Jan Withagen wrote:
> > Coredump available.... 61Mb compressed.
> > 
> > system contains a de card, which is correctly identified as GIANT-LOCKED. The
> > card is not connected. Next time I open up the box, I'll remove it.
> 
> Well this is no big surprise.... de(4) isn't locked properly and
> probably never will be. 

However, locking problems with if_de can't (or shouldn't) explain the
panic in question :-).  We're probably looking either at a SACK problem,
or a TCP locking problem.  I need to review the TCP callouts, delivery,
and reassembly code and make sure all is well.  I also need to make sure
that I really did merge all the relevant bits of the netperf patch
relating to TCP -- there are some changes left, but I think they are
purely layout changes.  If you want to give it a spin, given some
background in TCP, feel free :-).

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Principal Research Scientist, McAfee Research