panic: sleeping thread & bufwrite: buffer is not busy???

[Roman Divacky]

On Fri, Dec 12, 2008 at 10:38:56AM +0000, Robert Watson wrote:
> On Fri, 12 Dec 2008, Kostik Belousov wrote:
> 
> >>Unfortunately I cannot provide more debug information at this time
> >>because kernel was built without debugging options. (I will rebuild it
> >>if needed) However I can still provide some info:
> >>- kernel panic while loading modules, just after loding ZFS module (I
> >>have RAIDZ configuration) and after a couple of minutes without any
> >>visible action on the screen.
> >>- I have this panic with *every* build I made after 7 Dec 2008, but I
> >>don't remember wchich day exactly I have experienced that for the first
> >>time.
> >>- For now I'm using kernel builded 7 Dec 2008 and no panic seen at all.
> >
> >You are mixing the issues without a reason. To claim that you problem is 
> >similar, you need to show the similar backtrace. The panic shown is the 
> >late manifestation of a problem, it is kind a catch-all for some sort of 
> >locking issues.
> 
> This is the second report of weird rwlock-related panics in a week.  We 
> should read the code on this one closely, but I can't help but notice that 
> it's similar to Roman's report of an rwlock-related panic.  Was there a 
> locking/scheduling change in the last week or two in -current that could 
> explain these symptoms?

I still have the vmcore from the crash... can it help?