lockdep: fix overflow in the hlock shrinkage code

There is a overflow by 1 case in the new shrunken hlock code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2008-08-11 12:34:42 +02:00 committed by Ingo Molnar
parent 3295f0ef9f
commit b42e737e57

View File

@ -191,7 +191,12 @@ struct lock_chain {
};
#define MAX_LOCKDEP_KEYS_BITS 11
#define MAX_LOCKDEP_KEYS (1UL << MAX_LOCKDEP_KEYS_BITS)
/*
* Subtract one because we offset hlock->class_idx by 1 in order
* to make 0 mean no class. This avoids overflowing the class_idx
* bitfield and hitting the BUG in hlock_class().
*/
#define MAX_LOCKDEP_KEYS ((1UL << MAX_LOCKDEP_KEYS_BITS) - 1)
struct held_lock {
/*