[RT XFS] BUG from lockdep in xfs

[Dave Chinner]

On Wed, Sep 09, 2015 at 07:44:51AM -0400, Brian Foster wrote:
> On Tue, Sep 08, 2015 at 11:54:07PM -0700, Austin Schuh wrote:
> > I'm running xfstests and got the following BUG with lockdep enabled.
> > I'm running the 4.1.6-rt5 kernel from TI's tree on a TI ARM chip.
> > 
> > Any ideas on what could be causing it, or if it is a real problem?
> > 
> > I see some patches in Dave's latest 4.3 pull request that discuss
> > lockdep.  Are there any ones there that are worth backporting to my
> > 4.1.6 kernel?
> > 
> 
> I suspect Dave's recent rework of the lockdep namespace bits is what you
> want:
> 
> 	0952c818 xfs: clean up inode lockdep annotations

Yes, that works around the issue that causes this:

> > [ 4357.394974] BUG: looking up invalid subclass: 8

i.e. that we have about 15 different subclass annotations for
different inode locking situations we need to shoe horn into 8
subclasses...

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com