Commit b42e737e authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

lockdep: fix overflow in the hlock shrinkage code 



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

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 3295f0ef

include/linux/lockdep.h

+6 −1
Original line number Diff line number Diff line
@@ -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 {

	/*