hard deadlock(?) on -current; some debugging info, need help

[Ted Faber]

On Sat, May 28, 2005 at 06:43:02AM +1000, Peter Jeremy wrote:
> On Fri, 2005-May-27 08:27:52 -0700, Ted Faber wrote:
> >> It might be useful to know some more details about that NFS mount
> >> (fsid 0x0600ff07).  Can you tell us the mount parameters and what the
> >> server is (OS type).
> >
> >Most o fthe nfs filesystems are automounted.  I'm on the machine now, so
> >I can't look at debugger output, but I can tell you that most of the NFS
> >mounts that I can imagine either psi or bash looking at are automounted.
> >The mount parameters are: timeo=8,retrans=9,intr
> 
> I didn't notice amd before.  If you can't avoid NFS, any chance of (at
> least temporarily) hard-mounting all the relevant filesystems and
> disabling amd?  amd acts as an NFS server to detect activity on the
> automount filesystems.  Both the backtraces you posted show that one
> process is blocked on an NFS request and amd is blocked on ufs.  The
> locks on the second backtrace show that the bash waiting on an NFS
> request is a root of the deadlock tree.  If that NFS request is
> supposed to be handled by amd, you close the deadlock cycle.

I think I've got it to the point where it's reproducible, and therefore
killable. :-)

It does seem to be an amd interaction, which gives me a way to avoid it
until it is killed.  Details within the hour.

Thanks again for your suggestions.

-- 
Ted Faber
http://www.isi.edu/~faber           PGP: http://www.isi.edu/~faber/pubkeys.asc
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