Re: 2.6.33-rc3-mmotm0106 - BUG: MAX_LOCKDEP_KEYS too low!

[Peter Zijlstra <peterz@infradead.org>]

On Wed, 2010-01-13 at 01:22 -0500, Valdis.Kletnieks@vt.edu wrote:
> Seen in my dmesg output - I wasn't even home at the time, so my
> laptop was basically idle.
> 
> [ 7777.019267] dell-wmi: Received unknown WMI event (0x11)
> [ 8190.620401] BUG: MAX_LOCKDEP_KEYS too low!

> If I'm hitting MAX_LOCKDEP_KEYS after just a few hours on a mostly-idle
> laptop, should it be set higher?

I'm wondering what's eating all those classes, it there a lot of module
loading/unloading happening?

Does something like the below give any clues?

---
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 5feaddc..90b9428 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -761,6 +761,7 @@ register_lock_class(struct lockdep_map *lock,
unsigned int subclass, int force)
 	debug_atomic_inc(&nr_unused_locks);
 	class->key = key;
 	class->name = lock->name;
+	printk(KERN_EMERG "LOCK CLASS: %s\n", lock->name);
 	class->subclass = subclass;
 	INIT_LIST_HEAD(&class->lock_entry);
 	INIT_LIST_HEAD(&class->locks_before);