Re: panic: System call lstat returning with 1 locks held

On Tue, Feb 05, 2008 at 06:00:33PM +0100, Attilio Rao wrote:
> 2008/2/5, Attilio Rao <attilio_at_freebsd.org>:
> > 2008/2/5, Yar Tikhiy <yar_at_comp.chem.msu.su>:
> >
> > > BTW, I seem to be hitting yet another lockmgr-related panic.
> >  >
> >  >  My system won't reboot under certain conditions: it'll panic instead
> >  >  in vfs_unmountall().  Namely it will panic if I reboot from single-user
> >  >  mode while it'll reboot OK from multi-user mode.  I have no idea
> >  >  yet about the exact reason for the behaviour.  The output from kgdb
> >  >  attached.
> >  >
> >  >  Note that this panic shouldn't be NTFS-related as I can trigger it
> >  >  by typing `reboot' immediately after booting into single user.
> >
> >
> > Yes, sorry for this.
> >  I know of this and I alredy patched my tree.
> >  I did the WITNESS stuff based on the assumption drained lock will
> >  never be release while they are. Unmounting is currently the only one
> >  consumer of LK_DRAIN I know of and I just need to do a WITNESS_LOCK()
> >  over there.
> >  I will provide you an updated patch about this problem and another one
> >  found by kris_at_.
> >
> >  I will look later at the backtrace so we can go on.
> 
> More specifically, here is the "fixed" version:
> http://www.freebsd.org/~attilio/witness_lockmgr2.diff
> 
> (against stock -CURRENT).
> Kris and me tested (rather) this version and I found it reliable, so I
> want to commit to CVS in a couple of hours.
> If you can add any other feedback to it, I would be very happy.

Feedback 1: The panic before reboot is gone.  Thanks a lot!
Now returning to the NTFS issue, stay tuned... :-)

-- 
Yar