This routine is only used together with lockdep for nested locking.
The number of lock subclasses is limited to 8 as defined in lockdep.h
Emit a warning if the adapter depth exceeds the maximum number of
lockdep subclasses.
Signed-off-by: Bartosz Golaszewski <bgolaszew...@baylibre.com>
---
drivers/i2c/i2c-core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index c9b8df8..75cefa8 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1342,6 +1342,9 @@ unsigned int i2c_adapter_depth(struct i2c_adapter
*adapter)
while ((adapter = i2c_parent_is_i2c_adapter(adapter)))
depth++;
+ WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES,
+ "adapter depth exceeds lockdep subclass limit\n");
+
return depth;
}
EXPORT_SYMBOL_GPL(i2c_adapter_depth);
--
2.7.4
