Fatal trap 12: page fault while in kernel mode

[Yuri Khotyaintsev]

On Friday 02 December 2005 14.54, John Baldwin wrote:
> On Friday 02 December 2005 05:00 am, Yuri Khotyaintsev wrote:
> > I have the following panic occurring several times a week. The machine is
> > an NFS server, and it usually panics early in the morning, when first
> > people try to access it. After reboot it may work OK for 1-2 days, and
> > then panics again. I have tried changing memory and replacing disk which
> > was exported via NFS, but nothing helped :(
> >
> > Any suggestion on how to fix this panic will be very much appreciated !
>
> This panic (in propagate_priority) is usually caused when a thread goes to
> sleep while holding a mutex (which is forbidden).  If you enable INVARIANTS
> and/or WITNESS you should get a better panic, and with WITNESS you will
> even be warned when a thread goes to sleep while holding a mutex.  However,
> these options do introduce considerable execution overhead, and sometimes
> that overhead changes the timing enough to hide the race. :(

I am compiling a new kernel with INVARIANTS and WITNESS now. Will wait for a 
"better" panic ;-)

-- 
Dr. Yuri Khotyaintsev
Institutet för rymdfysik (IRF), Uppsala