[PATCH] locking/lockdep: Don't complain about wrong name for no validate class

From: Sebastian Andrzej Siewior
Date: Fri May 17 2019 - 17:24:59 EST


It is possible to ignore the validation for a certain log be using
lockdep_set_novalidate_class()

on it. Each invocation will assign a new name to the class it created
for created __lockdep_no_validate__. That means that once
lockdep_set_novalidate_class() has been used on two locks then
class->name won't match lock->name for the first lock triggering the
warning.

Ignoring changed non-matching ->name pointer for the
__lockdep_no_validate__ class.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
kernel/locking/lockdep.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index d06190fa50822..38be69d344f7f 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -731,7 +731,8 @@ look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass)
* Huh! same key, different name? Did someone trample
* on some memory? We're most confused.
*/
- WARN_ON_ONCE(class->name != lock->name);
+ WARN_ON_ONCE(class->name != lock->name &&
+ lock->key != &__lockdep_no_validate__);
return class;
}
}
--
2.20.1