Panic: witness_warn (r191682; shared rw udpinp (udpinp)...netinet6/udp6_usrreq.c:360)

[Robert Watson]

On Thu, 30 Apr 2009, David Wolfskill wrote:

> Build machine crashed on boot of r191682:
>
> ...
> GEOM_LABEL: Label ufsid/48fa940b4445475f removed.
> fxp0: link state changed to UP
> suspending ithread with the following locks held:
> shared rw udpinp (udpinp) r = 0 (0xc5ac4f3c) locked @ /usr/src/sys/netinet6/udp6_usrreq.c:360
> panic: witness_warn
> cpuid = 1
> KDB: enter: panic
> [thread pid 12 tid 100008 ]
> Stopped at      kdb_enter+0x3a: movl    $0,kdb_why
> db>
>
> I started to paste the output of "show witness" in here, but it got to be 
> sufficiently lengthy that I thought it better to save it for private mail or 
> a follow-up if it's really wanted.

This falls into the category of "unlikely software bugs" -- is there any 
chance this machine is overheating or has memory problems?  "show alllocks" 
would be helpful on general principle, though.

Robert N M Watson
Computer Laboratory
University of Cambridge