panic on 5.2 BETA: blockable sleep lock

Stefan Ehmann shoesoft at gmx.net
Fri Nov 28 01:39:29 PST 2003


On Fri, 2003-11-28 at 10:31, Stefan Ehmann wrote:
> On Fri, 2003-11-28 at 01:02, Don Lewis wrote:
> > On 27 Nov, Stefan Ehmann wrote:
> > > On Wed, 2003-11-26 at 08:33, Don Lewis wrote:
> > >> The problem is that selrecord() wants to lock a MTX_DEF mutex, which can
> > >> cause a context switch if the mutex is already locked by another thread.
> > >> This is contrary to what bktr_poll() wants to accomplish by calling
> > >> critical_enter().
> > > 
> > > Strange enough that does not seem to happen with a kernel built without
> > > INVARIANTS and WITNESS. Does this make any sense or is this just by
> > > chance?
> > 
> > You might try the patch below with WITNESS enabled.  I don't have the
> > hardware, so I can't test it.  It compiles for me, but for all I know it
> > could delete all your files if you run it.
> 
> Unfortunately, after running the patched kernel some time I got a
> slightly different panic:

Please ignore the message above - this was the panic from an unpatched
kernel - I was debugging the wrong core.

Thanks again for quick help.



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