diff options
Diffstat (limited to 'kernel/lockdep.c')
| -rw-r--r-- | kernel/lockdep.c | 39 | 
1 files changed, 39 insertions, 0 deletions
diff --git a/kernel/lockdep.c b/kernel/lockdep.c index ea9ee4518c3..7981e5b2350 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2998,6 +2998,42 @@ EXPORT_SYMBOL_GPL(lockdep_init_map);  struct lock_class_key __lockdep_no_validate__; +static int +print_lock_nested_lock_not_held(struct task_struct *curr, +				struct held_lock *hlock, +				unsigned long ip) +{ +	if (!debug_locks_off()) +		return 0; +	if (debug_locks_silent) +		return 0; + +	printk("\n"); +	printk("==================================\n"); +	printk("[ BUG: Nested lock was not taken ]\n"); +	print_kernel_ident(); +	printk("----------------------------------\n"); + +	printk("%s/%d is trying to lock:\n", curr->comm, task_pid_nr(curr)); +	print_lock(hlock); + +	printk("\nbut this task is not holding:\n"); +	printk("%s\n", hlock->nest_lock->name); + +	printk("\nstack backtrace:\n"); +	dump_stack(); + +	printk("\nother info that might help us debug this:\n"); +	lockdep_print_held_locks(curr); + +	printk("\nstack backtrace:\n"); +	dump_stack(); + +	return 0; +} + +static int __lock_is_held(struct lockdep_map *lock); +  /*   * This gets called for every mutex_lock*()/spin_lock*() operation.   * We maintain the dependency maps and validate the locking attempt: @@ -3139,6 +3175,9 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,  	}  	chain_key = iterate_chain_key(chain_key, id); +	if (nest_lock && !__lock_is_held(nest_lock)) +		return print_lock_nested_lock_not_held(curr, hlock, ip); +  	if (!validate_chain(curr, lock, hlock, chain_head, chain_key))  		return 0;  |