diff options
| author | Bart Van Assche <bvanassche@acm.org> | 2019-04-15 10:05:38 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-04-16 08:21:51 +0200 |
| commit | 8b39adbee805c539a461dbf208b125b096152b1c (patch) | |
| tree | 1b3a4f8d2b60690a7c750c13d7016aff52880f74 | |
| parent | 618d919cae2fcaadc752f27ddac8b939da8b441a (diff) | |
| download | linux-8b39adbee805c539a461dbf208b125b096152b1c.tar.bz2 | |
locking/lockdep: Make lockdep_unregister_key() honor 'debug_locks' again
If lockdep_register_key() and lockdep_unregister_key() are called with
debug_locks == false then the following warning is reported:
WARNING: CPU: 2 PID: 15145 at kernel/locking/lockdep.c:4920 lockdep_unregister_key+0x1ad/0x240
That warning is reported because lockdep_unregister_key() ignores the
value of 'debug_locks' and because the behavior of lockdep_register_key()
depends on whether or not 'debug_locks' is set. Fix this inconsistency
by making lockdep_unregister_key() take 'debug_locks' again into
account.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: shenghui <shhuiw@foxmail.com>
Fixes: 90c1cba2b3b3 ("locking/lockdep: Zap lock classes even with lock debugging disabled")
Link: http://lkml.kernel.org/r/20190415170538.23491-1-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | kernel/locking/lockdep.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index e16766ff184b..e221be724fe8 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -4907,8 +4907,9 @@ void lockdep_unregister_key(struct lock_class_key *key) return; raw_local_irq_save(flags); - arch_spin_lock(&lockdep_lock); - current->lockdep_recursion = 1; + if (!graph_lock()) + goto out_irq; + pf = get_pending_free(); hlist_for_each_entry_rcu(k, hash_head, hash_entry) { if (k == key) { @@ -4920,8 +4921,8 @@ void lockdep_unregister_key(struct lock_class_key *key) WARN_ON_ONCE(!found); __lockdep_free_key_range(pf, key, 1); call_rcu_zapped(pf); - current->lockdep_recursion = 0; - arch_spin_unlock(&lockdep_lock); + graph_unlock(); +out_irq: raw_local_irq_restore(flags); /* Wait until is_dynamic_key() has finished accessing k->hash_entry. */ |