Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fix from Ingo Molnar:
 "Fixes a crash when accessing /proc/lockdep"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Zap lock classes even with lock debugging disabled
This commit is contained in:
Linus Torvalds 2019-04-12 20:31:08 -07:00
commit 26e2b81977
1 changed files with 12 additions and 17 deletions

View File

@ -4689,8 +4689,8 @@ static void free_zapped_rcu(struct rcu_head *ch)
return;
raw_local_irq_save(flags);
if (!graph_lock())
goto out_irq;
arch_spin_lock(&lockdep_lock);
current->lockdep_recursion = 1;
/* closed head */
pf = delayed_free.pf + (delayed_free.index ^ 1);
@ -4702,8 +4702,8 @@ static void free_zapped_rcu(struct rcu_head *ch)
*/
call_rcu_zapped(delayed_free.pf + delayed_free.index);
graph_unlock();
out_irq:
current->lockdep_recursion = 0;
arch_spin_unlock(&lockdep_lock);
raw_local_irq_restore(flags);
}
@ -4744,21 +4744,17 @@ static void lockdep_free_key_range_reg(void *start, unsigned long size)
{
struct pending_free *pf;
unsigned long flags;
int locked;
init_data_structures_once();
raw_local_irq_save(flags);
locked = graph_lock();
if (!locked)
goto out_irq;
arch_spin_lock(&lockdep_lock);
current->lockdep_recursion = 1;
pf = get_pending_free();
__lockdep_free_key_range(pf, start, size);
call_rcu_zapped(pf);
graph_unlock();
out_irq:
current->lockdep_recursion = 0;
arch_spin_unlock(&lockdep_lock);
raw_local_irq_restore(flags);
/*
@ -4911,9 +4907,8 @@ void lockdep_unregister_key(struct lock_class_key *key)
return;
raw_local_irq_save(flags);
if (!graph_lock())
goto out_irq;
arch_spin_lock(&lockdep_lock);
current->lockdep_recursion = 1;
pf = get_pending_free();
hlist_for_each_entry_rcu(k, hash_head, hash_entry) {
if (k == key) {
@ -4925,8 +4920,8 @@ void lockdep_unregister_key(struct lock_class_key *key)
WARN_ON_ONCE(!found);
__lockdep_free_key_range(pf, key, 1);
call_rcu_zapped(pf);
graph_unlock();
out_irq:
current->lockdep_recursion = 0;
arch_spin_unlock(&lockdep_lock);
raw_local_irq_restore(flags);
/* Wait until is_dynamic_key() has finished accessing k->hash_entry. */