panic: _sx_xlock_hard: recursed on non-recursive sx newbus

[Sven Esbjerg]

On Sun, Aug 16, 2009 at 07:50:03PM +0100, Robert Watson wrote:
> 
> On Sun, 16 Aug 2009, Marc UBM wrote:
> 
> >While loading snd_hda for fun on my fileserver, I got the following panic 
> >(crashdump available for poking around):
> >
> >panic: _sx_xlock_hard: recursed on non-recursive sx newbus @ 
> >/usr/src/sys/kern/subr_bus.c:219
> >
> >Backtrace is attached.
> 
> Hi Marc--
> 
> This is most likely associated with the known "newbus" locking issues from 
> late-break MPSAFEty work on newbus for 8.0.  I understand that Attilio is 
> working actively on fixing this (CC'd).

You could try Attilio's patch:
http://people.freebsd.org/~attilio/hdac.diff

It fixed the panic I was having while loading the sound driver.


-Sven