Re: panic: in_pcblookup_local (?)

John Baldwin wrote:
> On Thursday, May 02, 2013 7:25:08 am Robert N. M. Watson wrote:
> > 
> > On 2 May 2013, at 11:42, Glen Barber wrote:
> > 
> > > Hmm.  Perhaps it would be worthwhile for me to rebuild the current
> > > kernel with DDB support.  It looks like the machine has panicked a few
> > > times over the last two weeks or so, but based on the timestamps of the
> > > crash dumps and nagios complaints, happened during the middle of the
> > > night when I would not have really noticed, or otherwise would have just
> > > blamed my ISP.
> > > 
> > > Two of the panics are ath(4) related.  One looks similar to the one
> > > referenced in this thread, similarly triggered by a CFEngine process.
> > > 
> > > In that case, the backtrace looks like:
> > > 
> > > #4 0xffffffff808cdbb3 at calltrap+0x8
> > > #5 0xffffffff807371d8 at in_pcb_lport+0x128
> > > #6 0xffffffff8073745a at in_pcbbind_setup+0x16a
> > > #7 0xffffffff80737d8e at in_pcbconnect_setup+0x71e
> > > #8 0xffffffff80737df9 at in_pcbconnect_mbuf+0x59
> > > #9 0xffffffff807bf29f at udp_connect+0x11f
> > > #10 0xffffffff80680615 at kern_connectat+0x275
> > > 
> > > Regarding DDB though, it would be rather difficult to access the machine
> > > if it drops to a DDB debugger session, since the machine acts as my
> > > firewall.
> > 
> > Thanks -- will take a look at the attached.
> > 
> > FWIW, though, I'm worried by the number of panics you are seeing, especiall
y 
> given that they involve multiple subsystems, and in particular, John's 
> observation about a potentially corrupted pointer. This makes me wonder 
> whether (a) you are experiencing hardware faults -- it would be worth running
 
> some memory/cpu/etc tests and (b) if we might be seeing a software memory 
> corruption bug of some sort.
> 
> Other users have reported this (Ian Lepore), and Peter Wemm can now reproduce
> these at will as well, so I think this is a software bug.  What might be 
> easiest if we can't figure this out from the crashdump is just to bisect the
> offending revision.

I've started a binary search.  I'll let you know what that turns up.

Ian

-- 
Ian Freislich